How to query on product defects

I have been accessing the Informix web site to use their product defect query tool in the techinfo section. I want to query on "page not found". I've tried the following: page not found: returns hits on "page" or "not" or "found" "page not found" and 'page not found': treats the quotes as literals. page and not and found: treats the ands as literals. page+not+found and page]not]found: also no good. The help section they provide did not shed any light on this. Does anyone know how to do this? Thanks.