The fastest way using spotlight is to add
kind:folder to the search term in the spotlight field.
You can use booleans, metadata tags like
date:yesterday and more as described in Specifying criteria in the Spotlight search field
I always forget about these and instead use the search window to build up a boolean criteria rather than use the default spotlight menu search (where all the other data detectors compete to provide you relevant matches)
Instead of command+space try option+command+space
Then click the circle + on the right by Save and override the "Any" with "Folder"
I don't know a way to automate or save this further as the default, but it's a way that will work on all Macs.