Maybe you have seen this, but I wrote a guide long ago on searching the forum directly (vs google as you mention). It allows far more control and filtering than a G based search.
I don’t have a specific guide for searching within a topic, but using the search tool at the top, with the “… in this topic” option is useful. This is also mentioned in the one reply to my FAQ above, via the “Ctrl + F” search tool if on Win/Mac with a keyboard.
Additionally, the “Summarize This Topic” option filters the list to the most read, liked, replied to comments and can be a bit of a “Cliff’s Notes” version of longer topics. It’s not perfect, but I use that sometimes if I don’t know the search term of interest for the “within topic” search.
