Coupon Code on Cart Page

From the documentation:
Coupon code

Users have option to enter coupon code for their order. After entering a valid coupon code, click on Apply Coupon button, the system will discount price to total of order based on properties of that coupon code.

But I cannot see any box to add a coupon on the cart page.
How do I add it?

The screen shot shows the problem

Hi again Ian,
EShop allow admin to turn coupon feature ON/OFF. I think it is OFF on your site now. Just need to go to back-end side of EShop, then go to System->Configuration, under Option tab, you will see option to turn it on. Please see attached image.
By the way, please post your questions in correct area. You should post it in EShop, not Pre-sales question here please.
Sincerely, Giang

Yes, that was the problem.
Thanks.

OK No problem Ian,
Don't hesitate to let me know if you need any more helps.
Sincerely, Giang