idlackage 0 Light Poster

Is there a way to have multiple search entries for one TreeView, each for a different column, or having one search entry handle all columns? The effect I'm looking for is (for example) having three columns, and thus typing into three search boxes to narrow down to the results that match all three.

I'm looking at set_search_equal_func(), but I don't get what I'm supposed to return/implement in order to set a certain row as part of the search and I can't find anything on it. (If anyone has an example for this, that would be great, thanks!)