拼音搜索用query_string可以高亮，为何用match_phrase就不能高亮了？

{

  "error" : {

    "root_cause" : [

      {

        "type" : "array_index_out_of_bounds_exception",

        "reason" : null

      }

    ],

    "type" : "search_phase_execution_exception",

    "reason" : "all shards failed",

    "phase" : "query",

    "grouped" : true,

    "failed_shards" : [

      {

        "shard" : 0,

        "index" : "pinyin_index",

        "node" : "gDlILShpRcaaiuzMO75Jcw",

        "reason" : {

          "type" : "array_index_out_of_bounds_exception",

          "reason" : null

        }

      }

    ],

    "caused_by" : {

      "type" : "array_index_out_of_bounds_exception",

      "reason" : null,

      "caused_by" : {

        "type" : "array_index_out_of_bounds_exception",

        "reason" : null

      }

    }

  },

  "status" : 500

}