Windows search very slow or uncomplete

I use to make a copy of my daily files (to have a backup on my home computer)With Windows XP, I use of course seach with a date = today result = all files are founded and it's quite quick (20s)With Windows Vista 1rst method searching in the indexed files result = only part of today files are found ! :( (probably because not yet indexed) 2nd method searching also in n on indexed files result = all files are find :) ... but it takes near 1/4 hours !So i wan't just to have the search as in Windows XP : all today files in 20s is good for me, How to do that in Vista ? May there is another solution to accelerates indexing ?Thanks for your help