If you mean that you deleted a Word document so that it went to the Recycle Bin and then used Erase Recycle Bin, the document should have been erased. You can use Windows Explorer > Search to check if any copies remain.
One caution though ... only the last copy sent to the Recycle Bin would have been erased. Word tends to create lots of temporary files and timed backups while you are working on the document. Although these are deleted when you close Word, the only way to erase all trace of them is to use Erase unused space on the drive.
I erased a word-document in the Waste-Paperbasket. Now I need to erase the document - how can I find it - or is there any way to erase the document on the hard-disk somehow ?