dunno why you're havin the problem, you mite be missing codecs. if you wanna diagnose the problem for playing video, try using videoinspector or gspot, they'll tell u whats wrong with the particular file. also try running the videos in VLC also known as VideoLanClient -is got inbuilt codecs so u dnt have to dwnload anythin extra- its the best video player availabe n it plays anythin n everythin.
as for more search results, u need to select relevant options in search feature - like display results from all speeds, all quality etc. you also mite have activated filters, check that out too and inactivate them.