So why aren't they showing up in Google Drive on your hard drive? The most likely explanation is you haven't selected certain folders for offline viewing.
Google gives you the option of selecting which folders you want to be able to open when your PC/Mac is not connected to the Internet. If you don't see a folder, it's possible you didn't select it to be synced to your hard drive.
To make sure it syncs in the future, wait until you are reconnected to the Internet and then go to Google Drive preferences (by clicking on the Google Drive icon in your system tray (Windows) or task bar (Mac). One of the Sync Options is shared folders. Make sure you have selected the folders you want available for offline viewing/editing. The screenshot, below, shows what the pane looks like.
Note that files that are not in a folder are always synced for offline viewing.