The suppliers cannot yet see the documents. This is likely because you still need to grant access to the suppliers. You can do this by completing the following steps: 

1. Open the solicitation (RFP, ITB, RFQ)
2. Navigate to Content in the left menu.
3. Click on Not visible for suppliers at the top right.
4. Click on Make visible for suppliers.   
5. You can also choose to send a notification to the suppliers that the Content has become visible.

See also: "Will the Content become visible automatically when I have set up a schedule?"