You may have noticed that on some of the screens Varibill is extremely slow due to the volume of data being loaded. (This happens to me quite often on Data Maintenance)
To speed up searches, I would suggest you add the columns / remove the columns you'd like to see once your search results are displayed, before actually performing the search (using the Column Selector). The same goes for groupings. This doesn't speed up the return of the results necessarily, but I find it faster to work with once the results are displayed.