Using the top_hits aggregator

es-sample

curl -XDELETE "http://localhost:9200/personsearch"
curl -XPUT "http://localhost:9200/personsearch" -d'
{
  "settings": {
    "index": {
      "analysis": {
        "analyzer": {
          "idx_analyzer": {
            "tokenizer": "CommaTokenizer",
            "filter": [
              "lowercase",
              "trim",
              "snowball",
              "stop",
              "XYZSynFilter"
            ]
          },
          "sch_analyzer": {
            "tokenizer": "standard",
            "filter": [
              "lowercase",
              "trim",
              "snowball",
              "stop"
            ]
          },
          "sch_comma_analyzer": {
            "tokenizer": "CommaTokenizer",
            "filter": [
              "standard",
              "lowercase",
              "trim",
              "stop"
            ]
          }
        },
        "filter": {
          "XYZSynFilter": {
            "type": "synonym",
            "synonyms": [
              "aids virus, aids, retrovirology, hiv"
            ],
            "expand": true,
            "ignore_case": true
          }
        },
        "tokenizer": {
          "CommaTokenizer": {
            "type": "pattern",
            "pattern": ","
          }
        }
      }
    }
  },
  "mappings": {
    "employees": {
      "properties": {
        "fullName": {
          "type": "string",
          "index_analyzer": "idx_analyzer",
          "search_analyzer": "sch_analyzer"
        },
        "specialty": {
          "type": "string",
          "index_analyzer": "idx_analyzer",          
          "search_analyzer": "sch_analyzer"
        }
      }
    }
  }
}'
curl -XPUT "http://localhost:9200/personsearch/employees/1" -d'
{
  "fullName": "Don White",
  "specialty": "Adult Retrovirology, aids, hiv"
}'
curl -XPUT "http://localhost:9200/personsearch/employees/2" -d'
{
  "fullName": "Don White",
  "specialty": "general practitioner, physician, general, primary care"
}'
curl -XPUT "http://localhost:9200/personsearch/employees/3" -d'
{
  "fullName": "Don White",
  "specialty": "icu, er"
}'
curl -XPUT "http://localhost:9200/personsearch/employees/4" -d'
{
  "fullName": "Terrance Gartner",
  "specialty": "oncology, cancer, research, tumor, polyp, icu"
}'
curl -XPUT "http://localhost:9200/personsearch/employees/5" -d'
{
  "fullName": "Terrance Gartner",
  "specialty": "physician, general, GP, primary care, aids, icu"
}'
curl -XPUT "http://localhost:9200/personsearch/employees/6" -d'
{
  "fullName": "Terrance Gartner",
  "specialty": "emergency care, icu, ambulance, er, urgent"
}'
curl -XPUT "http://localhost:9200/personsearch/employees/7" -d'
{
  "fullName": "Carter Taylor",
  "specialty": "neurosurgery, brain surgery, brain tumor"
}'
curl -XPUT "http://localhost:9200/personsearch/employees/8" -d'
{
  "fullName": "Carter Taylor",
  "specialty": "trauma, icu, emergency care, ER, urgent care"
}'

curl -XGET "http://localhost:9200/personsearch/employees/_search?pretty=true" -d'
{
  "query": {
    "match": {
      "_all": "icu"
    }
  },
  "aggs": {
    "most-rel-agg": {
      "terms": {
        "field": "fullName",
        "order": {
          "top_hit": "desc"
        }
      },
      "aggs": {
        "most-rel-profile": {
          "top_hits": {}
        },
        "top_hit": {
          "max": {
             "script": "_doc.score"
          }
        }
      }
    }
  }
}'