GET /you_path/_search
{
   "size": 5,
   "_source":["expected_key1","expected_key2"],
   "query": {
      "bool": {
         "must_not": [
            {
               "term": {
                  "expected_key": expected_value
               }
            }
         ],
         "should": [
             {
                "term": {
                    "expected_key": expected_value
                }
            }
        ]
      }
   }
}