How to get outer object in elasticsearch from highlightfield - elasticsearch

Question

I have some documents like this:
{
"content": "DocumentFile",
"title": "no title",
"post_id": "18",
"url": "http://localhost/wp/?p=18",
"attachments": [{
"content": "Hi this is extrach data of file",
"hash": "UPR9BC57IW3PUNTQ3LP79Q6UN0V3ZR7AAFJNUFGH",
"name": "file."
}],
"isDeleted": "false",
"__creationdDate": "1456758952671"}
and I initialize elastic Search mapping so:
{
"post": {
"properties": {
"content": {
"type": "string",
},
"title": {
"type": "string",
},
"url": {
"type": "string",
},
"post_id": {
"type": "string",
"fields": {
"raw": {
"type": "integer",
"index": "not_analyzed"
}
}
},
"attachments": {
"type": "nested",
"include_in_parent": true,
"properties": {
"hash": {
"type": "string",
"analyzer": "vira_analyzer"
},
"name": {
"type": "string",
"analyzer": "vira_analyzer"
},
"content": {
"type": "string",
"analyzer": "vira_analyzer"
}
}
},
"_uid": {
"type": "string",
"analyzer": "vira_analyzer"
}
}
}}
and I add title,content,attachments.name , attachments.content to highlightfields
I search data in this document
it is in attachments.content and elasticsearch find it
now i want to get hash code of this attachment, what should i do ?
is there any option that elastic search give me the block of the attachment that have search query in name or content ??
by this:
Text[] highlightFragments = hitHighLights.get(field).getFragments();
elastic search me just the content field of that attachment. I want all of that block, some thing like this:
{
"content": "Hi this is extrach data of file",
"hash": "UPR9BC57IW3PUNTQ3LP79Q6UN0V3ZR7AAFJNUFGH",
"name": "file."
}
(a way is to get source of that document and search in it but it is not good because the speed decrease a lot.)