Try this: Enable developer options/mode:
Settings>My device>All Specs> tap on the Miui version tab many times until it says developer mode enabled.
then follow these steps: http://en.miui.com/thread-1319107-1-1.html
you can skip step one on the link as you already enabled developer mode.
Best of luck!
************************EDIT************************************************
Looks like the manage app is missing so you cannot.... Sorry....
Second space perhaps?
http://en.miui.com/thread-293812-1-1.html
I have not played with this feature....
it's located in the XiaomiEU Tools app.
The developer Method doenst work. I dont see "Users" in Settings
Second space works but i need the multiple users option. Is there any solution for this? Second space wont help me...
Thanks