I use Tampermonkey[1] with the "Google Hit Hider by Domain"[2] plugin to de-crapify my search results.
In spite of the name, it works on all search engine sites I've tried it on; Google, Startpage, DuckDuckGo, Qwant. It adds a "Block" button beside each search result which allows you to block sites from appearing in that particular search result. Or to 'perma-ban' them from ever showing in future search results.
No affiliation. Just a satisfied customer.
[1] https://www.tampermonkey.net
[2] https://greasyfork.org/en/scripts/1682-google-hit-hider-by-d...
Unfortunately it can't do anything about search results returning precisely the opposite of what you searched for; eg.
SEARCH: "How to completely uninstall XXX from YYY"
RESULT: "How to install XXX on ZZZ"
SEARCH: "How to completely +uninstall -install +XXX +from -on +YYY -ZZZ
RESULT: "Install YYY on ZZZ with this howto"
[Insert sound of computer being thrown across room]
And, while I'm on the subject, my tuppence worth for the list. Fucking You-fucking-Tube being returned as the first dozen search results for some crappy one liner which you've forgotten and need to look up quickly...
SEARCH: "cheatsheet keyboard shortcut for function Z in app Y"
WHAT I WANT THE SEARCH TO RETURN: "App Y Keyboard shortcut cheatsheet"
WHAT THE SEARCH ACTUALLY RETURNS: [almost an entire page of] "Take zen ninja mastery of Application Y in minutes by learning this arse-sum keyboard shortcut!" --a 45 minute unedited epic, filmed by a monosyllabic arsehole on a shaking, continually auto-focussing phone camera, orientated vertically. Featuring 20 minutes of "er... um... well..." mumbling at the beginning, telling the viewer how "arse-sum" this keyboard shortcut is going to be --if the fucker ever gets around to actually showing you it!
Followed by the actual clicking of the shortcut which the narrator manages to do while the camera is pointed at the wrong part of the screen and out of focus.