Click "Manage Trash" at the bottom of the REVIEW tab. Select the document(s) you would like to retrieve and click "Restore" at the top of the page.
Go to the main DOCUMENTS page and click the trash icon. Select the document(s) you want, and click "Restore" at the top of the page.
Note: The option to restore trashed documents will only be shown for the timespan applied to the database. The default time to delete the trash is 90 days. To change this setting follow the steps below.
Go to SETTINGS > General and click "Edit" under Delete & Trash. Input the days you would like to keep trashed documents in the database before being purged and click "Update".