How to flash twrp recovery and root xiaomi devices

1. Go to Settings-About phone-Find the MIUI VERSION, and tap on it for 5-10 times.
2. Go back to settings, sellect adittional settings. click on Developer options, and select enable
3. Find the option USB Debugging and enable it.
4. Download TWRP for your device  from the link
5. rename the file to 'recovery.img'
6. Install ADB
7. Open the folder where 'recovery.img' located.
8. Press and hold the shift key and right click in the folder
9. click on the option "Open command window here"

10. Boot your device on fastboot mode by turning it off,        pressing Power and the Volume Down buttons together,          and then connect it with your computer
11. First type this command "fastboot devices" to check if your device is into fastboot mode
12. Enter the command "fastboot flash recovery recovery.img"
13. Enter the command "fastboot boot recovery.img"
14. Your phone is now in TWRP recovery mode ( if it is not,the write on ADB: reboot recovery )
15. select Install Zip and click on 'SuperSu.zip'
16. corfirm the flash
17. reboot your device
18. DONT PANIC IF YOU DEVICE WONT TURN ON Sometimes need to wait.