I have a composite column that pulls the hierarchical entries from Tags, then splits and dedups them. Although intended to make the details pane look a bit neater, it has an extra effect that clicking on "Dogs" will show results from both Fiction.Animals.Dogs and Nonfiction.Animals.Dogs.
While my own template code is heavily customized for my own (very exacting and unreasonable) standards, there's a few examples here that do the same thing:
https://www.mobileread.com/forums/sh...d.php?t=168718