How to create compounding search filters

I’m using the MultiDirectory template (https://multidirectory.bubbleapps.io/) to build out a listings platform for a client, and need to adjust the search a little, however I am stuck.

Currently the user can select some filtering through 3 dropdown menus. If they select a Category, the results show fine. But if they then select Company Size, it resets the search results and now only shows Company Size filtered items.

What I would like to achieve is a compounding filter I guess, where if they select Category and then select Company Size, it shows results that fit within both filter criteria. If none exist, it says none.

If anyone could assist with how I can go about this, that would be greatly appreciated! I. cant seem to find anything on what I need