To search for a kit, search for iskit:=1 in the search bar. You can combine this with other search terms to narrow your search.
For example, to search for all kits:

Or perhaps you want to see all kits and bundles that have "skateboard" in the title:

Note: there is a current limitation with searching by kit inventory. Should you need to accomplish this, export out iskit:=1 then filter on the "stock" values.
