If you trash an item in ModQ, you can add it back into the App using a Social Search.
Navigate to the Library.
Select Social Search.
Select a Social Source (for example, Twitter or Instagram).
Enter a Hashtag.
Select the three dots in lower right hand corner of the content.
Click Publish to publish the content to the correct App.
WARNING: Do not select Bulk Clear in ModQ. If you select Bulk Clear, all content is removed from ModQ. To add the content back into ModQ, you must perform a social search for review and approval.