Not able to understand this Elasticsearch query - elasticsearch

Question

{
"query": {
"nested": {
"path": "product_vendors",
"query": {
"bool" :{
"must" : {
"bool" : {
"should" : [
{ "terms": {"product_vendors.manufacturer_style":["FSS235D-26","SG463-1128-5","SG463-2879-4"]}},
{ "terms": {"product_vendors.id":["71320"]}}
]
}
}
}
}
}
}
}
I have above elastic query, not able to understand this. Would anyone please explain what it means and what documents it will return?
Update : #christinabo , i tried your query , and results returned , but here some small issues , apart from the matched documents , two more additional documents are returning in those documents only vendor_id is matching , may i know why two extra unmatched documents are returning , do we need to some attribute or something to make sure strict search and return is allowed , can please suggest on this .

Answer 1

By observing the query, I can understand that there is a nested object in the data. I can imagine that it has this structure:
product_vendors: {
'id': 'the_id',
'manufacturer_style': 'some style'
}
In order to query a nested object, you need a nested query. This is why you have the nested keyword there. In a nested query, you need to specify the path (product_vendors) that leads to the embedded fields (id, manufacturer_style).
Then, the query defines a bool query with the must keyword, which means that the query which follows must appear in matching documents. In this case, what it must appear is another bool query, defined with the should keyword. This contains two terms sub-queries (one for manufacturer_style and one for id) and means that the matching documents should match one or two of them. Each sub-query queries the embedded field by specifying the whole route of the nested object, using the dot (i.e. product_vendors.manufacturer_style).
I would expect the query to return you the documents that match at least one of the terms queries, with the documents that match both to have higher score.
I hope that this explanation gives you an overall idea of this query.
More about bool queries from the documentation here.