Thanks calvinVeeZ for your advice.
Anyway before I sold my Mi5X, I took some pictures compare to my Mi5S, the result is good.
Dual camera of Mi5X works well.
If the unlocking is easier, I might buy it again.
I got my Mi5X the day before yesterday.
I spent whole Sunday afternoon to unlock bootloader but didn't succeed.
I installed VPN Turbo and selected China site but still got 10008 error.
I could not bind account and device together.
I sold my new Mi5X this morning to a guy who is sure that he can...
Just bought Mipad 3 three days ago.
During unlock process, it said the unit has been unlocked already.
After installed TWRP, I installed latest eu rom.
Everything seems alright but when I tried to install apps from play store.
It got stuck and kept saying "waiting for wifi".