Searching for a few fields from Set Collection

Elastic Stack Elasticsearch
2

This works well:

DELETE test 
PUT test/doc/1
{
	"level": ["DEBUG", "INFO"]
}
PUT test/doc/2
{
	"level": ["ERROR", "INFO"]
}
PUT test/doc/3
{
	"level": ["INFO"]
}
GET test/_search
{
  "query": {
    "bool": {
      "must": [
        {
          "term": {
            "level": {
              "value": "debug"
            }
          }
        },        {
          "term": {
            "level": {
              "value": "info"
            }
          }
        }
      ]
    }
  }
}

And gives:

{
  "took": 6,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "skipped": 0,
    "failed": 0
  },
  "hits": {
    "total": 1,
    "max_score": 0.5753642,
    "hits": [
      {
        "_index": "test",
        "_type": "doc",
        "_id": "1",
        "_score": 0.5753642,
        "_source": {
          "level": [
            "DEBUG",
            "INFO"
          ]
        }
      }
    ]
  }
}

First thing to do is to reproduce the problem with just a script like I did. Then try to understand what is wrong.
Here, I'm almost sure (but you did not share your mapping), that you are searching on a text field with default analyzer, using a term query with uppercase terms like DEBUG and INFO. Which is not going to work.