I found a thing that can be improved. It appears in case of images. The most visible is mainly for large images, long list, and location on a network drive. Sometimes it is necessary to wait 5 seconds to show results for a new search term.
But I’m not sure if it occurs only when you use SageThumbs or whether there would even have JPG images.
Anyway, I propose to interrupt retrieve information about entries in the list from the hard disk when you change the search term.