If you go and open this link, you will see a doc word file rendered in the page.
Now how can I pass my own files in url to open them using google docs viewer? Path could be something like :
\\SERVER_IP\My_Archive\2017\03\06\Test.docx
or
C:\inetpub\wwwroot\TestProject\UploadedFiles\Test.docx
The google viewer cannot access files on your local PC. It can open a document published anywhere in the Internet, where Google viewer can access it. You can upload your local file for example to google drive and use the google drive link after that.