You can find supplemental Documents attached for items (when available) between the MPN and Manufacturer columns in your RFQ Responses.
You will see a document icon in the DOC column when there are drawings available for a line item. If there are no drawings attached to that part, then the DOC column will be blank. When there are drawings available, you can quickly download each attachment by clicking on the DOC icon, and then on the specific file name that you want to download.
There is also the option to Download all shared Docs at once, which is available through the Project dropdown in the top left of your RFQ above your line items. It will automatically download all part documents.