Keyword List - Filter by multiple keywords

I mostly photograph birds, animals, insects, I use an extensive controlled vocabulary in a scientific hierarchical structure (mostly) for my key word list. I have, therefore, thousands of keywords. Which is fine.

My one major irriation with LR for asset management is the keyword list panel, which I use a lot to ensure the correct keyword(s) are applied, is that there is no boolean filter - unless you know better.

For example if I want to keyword several photgraphs as White-tailed Eagles - type 'White' into the keyword list box and unsurpisingly I get several hundred suggestions of animals and plants with white in the name. Folllow that up by typing 'tailed' and another 200 or so suggestions are added to the list. And 'Eagle' is just the icing on the cake.

I know I can use the FIND TEXT - ALL KEYWORDS in the search bar but that doesn't bring the actual keyword in my keyword list into play.

So - does anyone know of a way of adding an AND/OR filter to the key word list - plugin or some other whitchcraft. If not I'll add again to the ideas page - which I do once every millenia or so - in the hope that someone at Adobe who actually catalogues images might think, "Hang on, that's worth doing...".