Most of the popular general purpose search engines just dont seem to be able to find useful pages anymore, but there are still some great ones out there.

General Purpose
‎	small web search
Marginalia Search	independent DIY search engine that focuses on non-commercial content
SearXNG	free & open source, self hostable metasearch engine
Mwmbl	open source, community curated web search engine
Kagi Search (subscription based)	excellent paid general purpose search engine

Image Search
Yandex	yandex image search
SauceNAO	image source locator

Nerd Shit
Wolfgram Alpha	answer engine
SciSpace	search engine for scientific literature
Semantic Scholar	search engine for scientific literature
PubPeer	comments on papers