Improve results classification and search options

I got misleading results in some cases, for example you can see the images attached.

searching for 'tonguelid' on our wiki, we have as first results an attachment (a gif) with a score of 100%. The attachment title doesn't have 'tonguelid' on its own: scribing200px.gif. the only relation is with the owner page title: 'Located in xwiki » Technical Experience Center » Incisione laser per TongueLid'

others strange results are shown in image 2, where three users appears with 55% and 37% scores. they have a page with 'tonguelid' word in their watchlist

finally, with 28% and 24% scores, two pages with 'tonguelid' in titles appears, and the first one is the page that contains the attachment on top of the results

In my opinion, this classification doesn't reflects the real "weight" of the results.

If the searching algorithm won't be touched, is it possible to introduce a flag to choose if you want to search the attachments or not?