# Getting a result that I don't want. How to check why

**URL:** <https://discuss.elastic.co/t/getting-a-result-that-i-dont-want-how-to-check-why/125902>\
**Category:** Elasticsearch\
**Created:** [March 28, 2018, 10:00am UTC](https://discuss.elastic.co/t/getting-a-result-that-i-dont-want-how-to-check-why/125902 "2018-03-28T10:00:21Z")\
**Posts on this page:** 8\
**Page:** 1

<div class="post-metadata">

**Author:** ![Peter\_Steenbergen](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/peter_steenbergen/32/22888_2.png) [@Peter\_Steenbergen](https://discuss.elastic.co/u/Peter_Steenbergen)\
**Post date:** [March 28, 2018, 10:00am UTC](https://discuss.elastic.co/t/getting-a-result-that-i-dont-want-how-to-check-why/125902/1 "2018-03-28T10:00:22Z")

</div>

Hi,

I am using ElasticSearch 6.1.3 and have the following situation.  
Let me start sharing the query I am using.

```
POST develop/_search
{
  "query": {
    "bool": {
      "must": [
        {
          "multi_match": {
            "query": "omega 7",
            "fields": ["merk.naam^2", "categorie.naam^14", "naam^70", "did_you_mean"],
            "operator": "and"
          }
        }
      ]
    }
  },
  "track_scores": true,
  "sort": [
    {
      "type.keyword": {
        "order": "asc"
      }
    },
    {
      "populariteitscijfer": {
        "order": "desc"
      }
    }
  ]
}

```

With this query I get the results I want based on the scores and all (omega 3 is not appearing).  
Seen in: [http://drops.3ws.nl/qstszh](http://drops.3ws.nl/qstszh)

But when I change "omega 7" to "omega 3" the omega 7 category is also showing.  
Seen in: [http://drops.3ws.nl/NWHLl5](http://drops.3ws.nl/NWHLl5)

I cannot figure out why this is happening. Since the reversal does not include that category.  
When I run the analyzer like this:

```
GET develop/_analyze
{
  "analyzer": "didYouMean",
  "text": ["omega 3"]
}

```

This is the result for it:

```
{
  "tokens": [
    {
      "token": "omega",
      "start_offset": 0,
      "end_offset": 5,
      "type": "<ALPHANUM>",
      "position": 0
    },
    {
      "token": "visolie",
      "start_offset": 0,
      "end_offset": 7,
      "type": "SYNONYM",
      "position": 0,
      "positionLength": 2
    },
    {
      "token": "3",
      "start_offset": 6,
      "end_offset": 7,
      "type": "<NUM>",
      "position": 1
    }
  ]
}

```

I am itching my head over this. Hope someone can help out.

Greetings,  
Peter

Edit::

This is the contents of the field: did\_you\_mean with the query:

```
{
    "_index": "development-2018032812",
    "_type": "doc",
    "_id": "categorie-485",
    "_score": 4.3321357,
    "fields": {
      "did_you_mean": [
        "Omega-7"
      ]
    },
    "sort": [
      "categorie",
      -9223372036854776000
    ]
  },
  {
    "_index": "development-2018032812",
    "_type": "doc",
    "_id": "categorie-1",
    "_score": 632.3207,
    "fields": {
      "did_you_mean": [
        "Omega-3"
      ]
    },
    "sort": [
      "categorie",
      -9223372036854776000
    ]
  }
```

---

<div class="post-metadata">

**Author:** ![abdon](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/abdon/32/9195_2.png) [@abdon](https://discuss.elastic.co/u/abdon)\
**Post date:** [March 29, 2018, 8:00am UTC](https://discuss.elastic.co/t/getting-a-result-that-i-dont-want-how-to-check-why/125902/2 "2018-03-29T08:00:51Z")

</div>

You can [add `"explain" : true` to a query](https://www.elastic.co/guide/en/elasticsearch/reference/current/search-request-explain.html), to see how the score for each hit was calculated. That should help you figure out why a certain document is a hit.

If that doesn't help, could you post the full documents with the IDs `categorie-485` and `categorie-1`, as well as your index settings and mappings (the output of `GET develop`), and I'll gladly take a look.

---

<div class="post-metadata">

**Author:** ![Peter\_Steenbergen](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/peter_steenbergen/32/22888_2.png) [@Peter\_Steenbergen](https://discuss.elastic.co/u/Peter_Steenbergen)\
**Post date:** [March 29, 2018, 8:54am UTC](https://discuss.elastic.co/t/getting-a-result-that-i-dont-want-how-to-check-why/125902/3 "2018-03-29T08:54:17Z")

</div>

Hello Abdon,

Thank you for helping me out.  
It was to many characters so i created a gist for it:

> <https://gist.github.com/petericebear/0dd705dd3e9d0e6124b9150972dd75d3>

Thanks in advance, greetings

---

<div class="post-metadata">

**Author:** ![abdon](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/abdon/32/9195_2.png) [@abdon](https://discuss.elastic.co/u/abdon)\
**Post date:** [March 29, 2018, 11:30am UTC](https://discuss.elastic.co/t/getting-a-result-that-i-dont-want-how-to-check-why/125902/4 "2018-03-29T11:30:32Z")

</div>

Thanks for posting the additional information.

You're getting back document `categorie-485` as a hit for the query `omega 3` because of the synonyms you have set up, specifically these synonym definitions: `visolie, omega 3` and `visolie, omega-3`. These synonyms are applied at index time as well as at query time.

At index time, the `did_you_mean` field of document `categorie-485` will contain the value of for example `naam` (through `copy_to`): The `naam` field contains the value `Omega-7`, which gets tokenized into:

```auto
GET develop/_analyze
{
  "analyzer": "didYouMean",
  "text": ["Omega-7"]
}

{
  "tokens": [
    {
      "token": "omega",
      "start_offset": 0,
      "end_offset": 5,
      "type": "<ALPHANUM>",
      "position": 0
    },
    {
      "token": "visolie",
      "start_offset": 0,
      "end_offset": 7,
      "type": "SYNONYM",
      "position": 0,
      "positionLength": 2
    },
    {
      "token": "7",
      "start_offset": 6,
      "end_offset": 7,
      "type": "<NUM>",
      "position": 1
    }
  ]
}

```

All of these terms will end up in the inverted index, including `visolie` (as a synonym of `omega`).

At query time, the `omega 3` query on the `did_you_mean` field will also query for the same `visolie` synonym, as you can see from the output of `_analyze` that you posted. That's why this document is a match: the query for the synonym `visolie` matches the document because of the term `visolie` (through synonyms).

Now, you should ask yourself if you really want to apply synonyms both at index time and at query time. Generally, that is not the case. It's double the work and it can lead to unexpected search results as you have experienced.

I'd go with query-time synonyms only. This is something you can achieve by setting up a `search_analyzer` that uses synonyms, and an `analyzer` that does not use synonyms. For the `did_you _mean_field` the mapping would become:

```auto
        "did_you_mean": {
          "type": "text",
          "analyzer": "standard", 
          "search_analyzer": "didYouMean"
        }

```

With that mapping, document `categorie-485` is no longer a hit for the query `omega 3`. But synonyms still work. A query for `visolie` will still return document `categorie-1`.

Synonyms are tricky to set up properly. If you want to read more I can really recommend the excellent book "[Relevant Search](https://www.manning.com/books/relevant-search)" by @softwaredoug that covers synonyms in great depth.

---

<div class="post-metadata">

**Author:** ![Peter\_Steenbergen](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/peter_steenbergen/32/22888_2.png) [@Peter\_Steenbergen](https://discuss.elastic.co/u/Peter_Steenbergen)\
**Post date:** [March 29, 2018, 11:45am UTC](https://discuss.elastic.co/t/getting-a-result-that-i-dont-want-how-to-check-why/125902/5 "2018-03-29T11:45:53Z")

</div>

Thank you for the helpful reply. I thought the AND operator was also triggered for the query in which 3 is not 7. Is there a reason that is not triggered for this kind of query?

Just bought the book and will read up on it. The solution you gave helped me out.

---

<div class="post-metadata">

**Author:** ![abdon](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/abdon/32/9195_2.png) [@abdon](https://discuss.elastic.co/u/abdon)\
**Post date:** [March 29, 2018, 11:48am UTC](https://discuss.elastic.co/t/getting-a-result-that-i-dont-want-how-to-check-why/125902/6 "2018-03-29T11:48:27Z")

</div>

Yes, there is an AND for `omega 3`, but it would not make sense to search for all synonyms with an AND. `omega AND 3 AND visolie` would probably not return any hits. Instead Elasticsearch will search for one of the synonyms. You can think of the query as: `(omega AND 3) OR visolie`.

---

<div class="post-metadata">

**Author:** ![Peter\_Steenbergen](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/peter_steenbergen/32/22888_2.png) [@Peter\_Steenbergen](https://discuss.elastic.co/u/Peter_Steenbergen)\
**Post date:** [March 29, 2018, 12:01pm UTC](https://discuss.elastic.co/t/getting-a-result-that-i-dont-want-how-to-check-why/125902/7 "2018-03-29T12:01:12Z")

</div>

Ah, and in this case it was visolie also for Omega 7.  
Thank you for the clarification.

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [April 26, 2018, 12:01pm UTC](https://discuss.elastic.co/t/getting-a-result-that-i-dont-want-how-to-check-why/125902/8 "2018-04-26T12:01:21Z")

</div>

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