Convert Facebook name to database name

My facebook acount name is D??ng Thu? Linh (Vietnamese).
After I log in my website by using Facebook acount, user data in database same as below:
user_login: Thuy-Linh-Duong
user_nicename: thuy-linh
display_name: Thuy Linh
first_name: Thuy Linh
last_name: Duong
* The name is converted to English
How to get first_name, last_name or display_name same as on Facebook (D??ng Thu? Linh not Duong Thuy Linh)