Some notes, for my reference.

https://www.inaturalist.org/pages/search+urls#multiple-places

On the above linked page, there are instructions for how to exclude specific places. They must be entered into the URL string as their place ID (which is a number string).

I have been having issues searching for new observations because the simple 'Description/Tags' box scoops up everything with the word 'knife', for example 'Big Knife Provincial Park'.

So I just add [&not_in_place=149037] to the URL string. Boom, no results from that location. Of course, if there were any observations from Big Knife with a Swiss Army knife in the photo, I would not see it.

This is the URL I tried:

https://www.inaturalist.org/observations?not_in_place=149037&not_in_project=swiss-army-knives-of-inaturalist&place_id=any&q=knife&subview=table&verifiable=any

I'm still having trouble though. It seems there are places with number strings and places with text strings. I'm not sure how they differ. Also, there are still some results for 'Big Knife Provincial Park' that appear in the search results. Is that because there are two different 'places' in the system?