Why don't shared docs appear in the shared docs folder?

Why don't shared docs appear in the shared docs folder?

I'm a newbie testing out document sharing with another newbie friend. We each shared a document with each other, and set them up as co-owners, but the shared docs don't appear in either of our shared docs folders. The only way to get to the shared doc is to go back to the external email account associated with the Zoho account (the message apparently doesn't go to the Zoho mailbox), and click the link to the doc. Then it appears, ready to edit. But there seems to be no way to get the shared files to appear in the shared docs folder. We always have to go back to the external email box, find and open the message, and click the link to get to it. That's a pretty roundabout procedure to have to go through just to get to the doc each time. Are we doing something wrong? Why don't shared docs appear in the shared docs folder?