Hi Renee,
You can achieve this by implementing custom functionality.
You can use the String split java action from the Community commons module to split your string based on the delimiter. The java action will return a list.
After you get the searchable keywords in the list you can iterate them and retrieve the appropriate list accordingly. The next step is to search the list with the keywords you can use the method I have mentioned in your other question( https://forum.mendix.com/link/questions/120795 )
The only Small change that you would be doing is retrieving all the lists before the loop and inside your loop use Filter with list operation and filter from the total retrieve list.
Hope this Helps!!