This is likely because of the term frequency (TF) in the doc. The repetition of the search terms in the document outweigh any exact matches with no repetition.
But the documentation says that Boolean similarity returns a score that is based on whether the query terms match or not, so I assumed that has nothing to do with TF.
Thanks for the options mentioned, but is there a way to extend default Boolean similarity and implement my own similarity that does exactly what I want? Because option 1 may still result with a suboptimal result, and option 2 can impose longer runs.
The problem I'm solving with Elasticsearch is to fuzzy match postal address, given the fact that addresses and receivers can be misspelled, there are aliases for addresses/receivers etc, and the main problem I'm dealing with is interference between primary and alternative town and street names.