If your office documents are stored on OneDrive (formerly SkyDrive), set up that account on your phone, and they will show up in the Office Hub. If you have been using Google Drive, you can download the docs you want to your computer as Office files, and then upload them to OneDrive to get to them from anywhere.
Transfer your files using a USB cable
Connect your old phone to your PC and drag and drop the office documents you want to transfer onto your PC. If you have the OneDrive desktop app, drag and drop the docs straight to the OneDrive folder for automatic upload. To access your office documents on your phone, from the Start, swipe left to App list and select Office > OneDrive.