Internal search categories not working as intended


I have set up internal search to collect query from URL, along with three defined category parameters.

Here is an example: search?q=Lorem&category=koeretoejer-og-autoudstyr&type=type+2&brand=brand+1

Query is collecting as intended, but categories is only collecting the very first one, which in this case is “category”. The other two are “type” and “brand”, but they are not showing up in report.

When I try to type in the categories in Administration, it seems to be buggy and not really responding correctly. Somehow I managed to enter the categories by typing, pushing dash and enter, but as I type, text is not showing.

Any idea how to solve this issue?