Using the SO search engine to look for questions and answers about
HTTPS gives plenty of results about HTTP, but articles about HTTP are not at the top of the list of relevant articles. Searching about
"HTTPS" (in quotes) gives what is expected.
More realistically, the search engine does not work well when looking for questions about redirecting HTTP to HTTPS. Querying without quotes gives useless results. Querying with quotes gives useful results. This also means that the Related questions links for questions about HTTPS are not as relevant as they ought to be.
I guess this is because the SO search engine does "stemming" of search terms: converting plural nouns to singular nouns, and such like. That is almost always the right thing to do for a search engine. But for searching about
HTTPS on SO (and perhaps other technical terms and on other SE sites, too) the precise word is important, and stemming is the wrong thing to do.
Expecting users to know they must search for "HTTPS" rather than HTTP seems unreasonable to me.
Could the search engine be configured so stemming was not done on words such as HTTP? If that functionality is already present, please could HTTPS/http be added to the list of words not porcessed by the stemming algorithm.