When using the search bar to look for a similar question before posting your own, how many results is it reasonable to check?
Is 50 or 100 search results reasonable enough to go through, when using a set of keywords in the search bar on Sololearn before you're convinced that a similar question has not been posted before? Or should you keep searching for more results?
That gives me an idea for finding Sololearn questions that have been deleted for whatever reason through moderator action. But on second thoughts, if they have been deleted, they're probably not worth looking at.
I try using different sorts and keyword combinations, but if it's pretty clear that the in-app search is just truncating relevant results (or just doesn't seem to understand what I want) I'll pop my web browser open and use Google or some other search engine, starting queries with "SoloLearn" as a keyword.
I think you would probably come up with your own give-up-and-let-a-better-search-bar-wielder-help threshold after that.
The only caveat is that Google shows you a snippet of what the posts say, but sometimes the posts are no longer available because the posts have been removed (but they still show up in search somehow...) so sometimes it can feel like you're so close yet so far! /agony