Regex search

Elastic Stack Elasticsearch
1

Hello, All

first I'm beginner with ES so sorry if my question will sound stupid.

I have problem to search file path with regex in query_string. (unfortunately due to way how app is written that's my only option)
seems that / in string is killing search as I can easily remove one char from my "word" and it will be found but if use string that is starting straight after / I get nothing.
same time if I use regexp query I get my data.

cs_uri_stem field contains:
/some/path/to/file.txt

Doesn't work (similar to Graylog generated search):
    curl -XPOST "http://10.0.0.20:9200/_all/_search" -d'
    {
      "from": 0,
      "size": 100,
      "query": {
        "filtered": {
          "query": {
            "query_string": {
              "query": "gl2_source_input:577281f853325c6c3ee5a3e4 AND cs_uri_stem:/.*file.*/",
              "allow_leading_wildcard": true
            }
          },
          "filter": {
            "bool": {
              "must": {
                "range": {
                  "timestamp": {
                    "from": "2016-06-30 22:26:03.475",
                    "to": "2016-06-30 22:31:03.476",
                    "include_lower": true,
                    "include_upper": true
                  }
                }
              }
            }
          }
        }
      },
      "sort": [
        {
          "timestamp": {
            "order": "desc"
          }
        }
      ]
    }'

    Works:
    curl -XPOST "http://10.0.0.20:9200/_all/_search" -d'
    {
      "from": 0,
      "size": 100,
      "query": {
        "filtered": {
          "query": {
        "regexp": {
            "cs_uri_stem": {
                "value": ".*file.*"
            }
        }
          },
          "filter": {
            "bool": {
              "must": {
                "range": {
                  "timestamp": {
                    "from": "2016-06-30 22:26:03.475",
                    "to": "2016-06-30 22:31:03.476",
                    "include_lower": true,
                    "include_upper": true
                  }
                }
              }
            }
          }
        }
      },
      "sort": [
        {
          "timestamp": {
            "order": "desc"
          }
        }
      ]
    }'
2

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