Search Based on the File Type.

With Google help, you could search file file with the certain type began PDF, HTML, DLL, TXT, TXT, DOC, EXE, and still many others that were other, but how searched this files quickly.
To look for the type file certain you could use keyword filetype:file extension. For example you looked for the type file PDF, typed to the google search box “filetype:pdf” (without quotation marks), afterwards results with the type file PDF will be put forward, but the search with keyword above possibly could not produce the search that was specific because results of the search only referred in the type file PDF .
If wanting to search more specific you could use keyword along with “inurl:word that was looked for filetype:extension that was looked for” for example you searched hacker with the type file pdf, then the keywords  became “inurl:hacker filetype:pdf” without quotation marks

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