How to force certain fields in mult_match to have exact match - elasticsearch

Question

I am trying to match the title of a product listing to a database of known products. My first idea was to put the known products and their metadata into elasticsearch and try to find the best match with multi_match. My current query is something like:
{
"query": {
"multi_match" : {
"query": "Men's small blue cotton pants SKU123",
"fields": ["sku^2","title","gender","color", "material","size"],
"type" : "cross_fields"
}
}
}
The problem is sometimes it will return products with the wrong color. Is there a way i could modify the above query to only score items in my index that have a color field equal to a word that exists in the query string? I am using elasticsearch 5.1.

Answer 1

If you want elasticsearch to score only items that meet certain criteria then you need to use the terms query in a filter context.
Since the terms query does not analyze your query, you'll have to do that yourself. Something simple would be to tokenize by whitespace and lowercase and generate a query that looks like this:
{
"query": {
"bool": {
"filter": {
"terms": {
"color": ["men's", "small", "blue", "cotton", "pants", "sku123"]
}
},
"must": {
"multi_match": {
"query": "Men's small blue cotton pants SKU123",
"fields": [
"sku^2",
"title",
"gender",
"material",
"size"
],
"type": "cross_fields"
}
}
}
}
}