I have just started to use the bookmark feature. It seems a short cut to previously identified "post(s)" that offer some significant reference/solution/approach.
As for searching generally, I see 2 types:
-search (possibly advanced) where you are looking for a specific item/topic that you know exists. You may know some keyword and/or the author and/or the time frame, but you know aspects of the result(s) you expect,
-search/browse with some keywords/concepts where you are looking for ideas/references/details to improve/establish some general facts to "educate/familiarize" yourself. This may involve browsing/reviewing several discovered sources and/or refining your browsing criteria and continuing this cycle. The actual search/browse path may be quite convoluted and meander through a series of related concepts/keywords (even antonyms) to bring the "general topic" into clearer focus.
I'm liking the search feature. I have not noticed it being slow.