You may be  looking for a search engine that can  search  only Documents files  for you if so your search ends here.With DocJax,a documents search engine, you can search many documents of PDF,PPT,DOC,XLS formats  with  preview  and even download them for free from there.

DocJax has integrated  Google and yahoo  search engines to generate the search results.

The tidy user interface of DocJax is very clean and tidy so you will love it.

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