The Search Filter doesn't work properly with Cloud Storage Chests (Inventory with scrollbar) since it always just searches in the currently visible items rather than searching for the item in the whole chest.
In order to search for items there, you have to scroll down.
Tested on a server with the newest versions of both Cloud Storage and Quark
I'm not entirely sure, which side this is on, so I will post this to both githubs.

Don't believe this is fixable