From your 'My Hub' page (please see below)
On the left hand side of your account, you will see the side menu in which you can select 'Contacts'.
Click a client profile
Followed by 'Assignments' from the list below the client profile picture and then 'Workouts'
If you then switch to 'Created' from the options at the top
You will be able to see any 'Created Workouts' which your client would have made themselves