For basic keyword searches. It’s not uncommon for search users to want inexact equivalencies, synonyms or conceptually close search results. (Search for cold, get back rhinovirus). Every user and use case has different definitions/tolerances of “this term appeared on the page”
It’s a complicated topic, without simple solutions. I wrote about it here.
https://opensourceconnections.com/blog/2018/12/07/synonyms-b...