Is it possible to create a custom search of two categories, one filtered and the other not?

[Arne]

More specifically, I would like to highlight both man-made drinking water stations and fountains with drinking water.

My first attempt: select both categories, then select drinking water = yes in the search editor. -> only such fountains were displayed

Second attempt: create two custom searchs, and activate both of them in the POI highlighter when needed. -> difficult to figure out

Ideally, it should be possible to filter categories separately.