Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu xanh » chieu sach, chieu sang, chieu tinh
nhung cong » dung cong, thong cong, hang cong
doi chieu » doc hieu, doi chi, ho chieu
manh tung » manh hung, thanh tung
cong tac » cong ty
tac toan » tap toan, tam toan, hach toan
toan ban » van ban

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: doi chieu xanh - ((thanh trung) OR (manh tung)) va nhung cong tac toan ban~.
• Adding a wildcard symbol may retrieve word variants: doi chieu xanh - ((thanh trung) or (manh tung)) va nhung cong tac toan ban*.