search results doesn't show file contents found and not highlighted

see how in this picture:
http://res2.windows.microsoft.com/re...10ab536484.jpg

in the search results, if the searched word is found inside a file, a few lines of text are show with the word highlighted.

i'm using windows 7 and this does not happen for me. if a word is found in file contents, i'll get it listed in the results, but it won't show me the context of it like in the picture.

what's wrong?

i think i figured it out
right click on your drive and go to properties.. check "allow files on this drive to have contents indexed"
when it is finished doing that...
go to control panel, indexing options, make sure the folders you want indexed are selected.....then go to advanced and rebuild the index

actually...i think this was the problem:

in windows explorer, go to folder options, search, uncheck "don't use the index when searching in file folders for system files"