Hello respected community. 

As I investigated, while adding lines to BOM, the product is searchable by two fields from product.product model: default_code and name. Such scope is too narrow and is not enough for me. I extremely need to be able to search products by description_sale field from product.template model.

Is there any way to extend search scope here while adding BOM lines? How do search widgets work? Any way to code this? How to make a relation?