How to find deleted items in NetDocuments
To restore a document that has been marked as deleted
On the document or documents you want to undelete, simply highlight the documents, then click on the MORE icon and click on undelete.

You will be prompted a location to restore those documents to ie a matter, however if you just ignore that and click on then the documents will be restored to their original profile values ie the orginal matter.
Further information can be found on the NetDocuments Support site on how to undelete (restore) a document
How to permanently delete the deleted document
Depending on your system generally Cabinet Administrators can do this.
Perform the same search for deleted items, select the items to delete, then click on More and click on DELETE
Further information can be found on the Netdocuments support site