I send this query and it works fine. It returns filtered data:

{
    "query": {
        "bool": {
            "filter": [
                {
                    "match": {
                        "lang": "en"
                    }
                }
            ]
        }
    },
    "size": 10,
    "from": 0,
    "sort": []
}

If I want to search with searchstring then it workst fine too:

{
    "query": {
        "query_string": {
            "query": "big size"
        }
    },
    "size": 10,
    "from": 0,
    "sort": []
}

But I can’t get data from elastic by filter and searchstring together:

{
    "query": {
        "query_string": {
            "query": "big size"
        },
        "bool": {
            "filter": [
                {
                    "match": {
                        "lang": "en"
                    }
                }
            ]
        }
    },
    "size": 10,
    "from": 0,
    "sort": []
}

I receive next error:

Error 400.
{"error":{"root_cause":[{"type":"parsing_exception","reason":"[query_string] malformed query, expected [END_OBJECT] but found [FIELD_NAME]","line":1,"col":76}],"type":"parsing_exception","reason":"[query_string] malformed query, expected [END_OBJECT] but found [FIELD_NAME]","line":1,"col":76},"status":400}

>Solution :

Your query needs to be restructured as shown below.

Query:

{
  "query": {
    "bool": {
      "must": [
        {
          "query_string": {
            "query": "big size"
          }
        }
      ],
      "filter": [
        {
          "match": {
            "lang": "en"
          }
        }
      ]
    }
  },
  "size": 10,
  "from": 0,
  "sort": []
}