IPad Mini 2 - Adobe Acrobat App Google Drive Sync

I just downloaded the Adobe Acrobat app onto my IPad Mini 2. I would like to use the app to do all of my class readings (pdfs). I uploaded all of my pdf files onto my google drive and was hoping to sync this to the Adobe Acrobat app. I was able to successfully do this with dropbox but not with google drive. Google Drive (along with dropbox) shows up as possible options for syncing but for some reason when I click 'done' for google drive nothing syncs.