XP text search

I find that if I search for a text within an Excel file (*.xls) in Windows 98 I find it okay, yet if I do the same search on the same file in WIndowsXP Pro I get no results. What do I ned to reconfigure? I downloaded the Powertoys tweak tool but I don’t see anywhwere where I can make a change to searching, HEEEEELP?