Sharepoint online currently has the function to do a multiselect on filtering of particular column when you are using a list webpart. I was able to use a query string webpart to filter one value, but I was not able to trigger it to filter multiple. Does anyone know the correct syntax for doing this?
I personally tried the following but they didn't work (Filter is the column name denoted here):
?Filter=a&Filter=b
?Filter=a&b
?Filter=a,b
?Filter=a;b
EDIT: Some of the answers may have misunderstood intent. The intent is to activate something similar to a true "or" relationship. The list webpart obviously have this as a built in function. I just need the proper syntax to pass in connections properly to activate the filtering mechanism.
Thanks!

