When I use filter query while sort with _score, will ES read tf/idf to cacculate score?

Elastic Stack Elasticsearch
1

like query below:
"query":{"filtered":{"query":{"match":{"productName":{"query":"123","type":"boolean"}}},"filter":{"bool":{"must":{"term":{"venderId":"24305"}}}}}},"sort":[{"_score":{}}

will ES read tf/idf to cacculate score?

2

The score will be calculated for the query part of your filtered query. Filters don't affect scoring though.

You can debug this adding the explain flag to your search call:

GET /_search?explain=true