Keyword filter

Hey guys, me again.

Situation: I am aggregating items from different sources, all listing up on one page. Now I want to add different sub-pages, each one only showing items with defined topics. Example: from all sports blogs, I want an item list only showing articles which deal with “nutrition” on a single page named “nutrition”.

Problem #1: I can not use the category-add on, as not all sources are using the same category-definitions to filter.

Problem #2: I can not use the GLOBAL keyword filter, because it works for the complete import, not for the listing of single articles

Problem #3: Using the keyword filter with shortcode only allows me to use ONE keyword, not more or even a combination.

Problem #4: When I do use a keyword filter in shortcode, sometimes it also shows items from blogs which do NOT include the term – because their feed finds it somewhere else nearby on that blog page

Any suggestions or ideas?
https://lauf-blogger.de/

THANKS!