anchor.diff:          "common": {
               "body": {
                   "query": "nelly the elephant as a cartoon",
  -                    "cutoff_frequency": 0.001,
  -                    "low_freq_operator": "and"
  +                "cutoff_frequency": 0.001,
  +                "low_freq_operator": "and"
               }
           }
       }
  
positive.code:         "common": {
              "body": {
                  "query": "nelly the elephant not as a cartoon",
                      "cutoff_frequency": 0.001,
                      "minimum_should_match": {
                          "low_freq" : 2,
                          "high_freq" : 3
                      }
              }
          }
      }
  
negative.code:         "common": {
              "body": {
                  "query": "how not to be",
                  "cutoff_frequency": 0.001,
                  "minimum_should_match": {
                      "low_freq" : 2,
                      "high_freq" : 3
                  }
              }
          }
      }
  