nested query turned filter

nested filter

{
  "size": 100,
  "query": {
    "filtered": {
      "query": {
        "multi_match": {
          "query": "gospel",
          "fields": [
            "title.raw^60",
            "authors.raw^40",
            "subjects.raw^20",
            "title",
            "authors",
            "subjects"
          ]
        }
      },
      "filter": {
          "bool": {
            "must": {
              "nested": {
                "path": "clients",
                "filter": {
                  "bool": {
                    "must": [
                      {
                        "term": {
                          "clients.email": "foo@railsdog.com"
                        }
                      }
                    ]
                  }
                }
              }
          }
        }
      }
    }
  }
}