How to delete a document in SharePoint
i) Navigate
to the library where the items (or documents) are located.
ii) Hover
over the document to display the check box and enable it.

iii) Repeat
the previous step for each item you want to delete.
iv) Either
press the Delete key on the keyboard or on the Ribbon, select the Files or
Items tab, and then click the Delete Document icon (X) in the Manage
group.

v) Click
OK to confirm deleting the items to the Recycle Bin.