I know a common complaint is search engine x fails at finding info for knowledge domain y, usually something technical that in the overall lexicon is ambiguous

I know a common complaint is search engine x fails at finding info for knowledge domain y, usually something technical that in the overall lexicon is ambiguous with something more generic/popular. I wonder if a good solution to this is to use one of the smaller open engines in a private instance and just submit the handful of sites you know have the relevant info?