The same was happening to us in the Astrobe forum that we administrate. This has now been fixed - try searching for Component Pascal on this forum and on the Astrobe forum to see the difference:The following words in your search query were ignored because they are too common words: ....
http://www.astrobe.com/forum
Fortunately the solution was simple:
1. Change the Common word threshold in Search settings to 0%.
2. Delete and then Create the search index in Maintenance > Search Index