Multidropdown to repeating group


Imagine a craigslist type of marketplace. You go on, and you want to search different types of stuff, which are shown in a multidropdown. When you pick say 3 types of stuff, you want the a repeater group to show all listings from those three types of stuff.

Right now, I have a search “do a search for” for the multidropdown’s value, but it only shows the listings when there is one type of stuff chosen. When I pick two or 3 types of stuff, the repeater doesn’t show. Is there a way to have the repeater show all listings from the 3 types of stuff?

Also, when there is nothing chosen in the multidropdown, I would like the repeater to show listings from all types of stuff.

Any advice is much appreciated!