Perhaps you should try some spelling variations:
phuong cong » phuong dong, phong cong, phung cong
chieu tinh » trieu tinh, lieu tinh, chau tinh
banh trang » hanh trang, ban trang, banh rang
doi chieu » doc hieu, doi chi, ho chieu
va phuong » va thuong, cac phuong
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.

• Performing a fuzzy search may retrieve terms with similar spellings: doi chieu tinh - ((banh trang) or (canh tranh)) va phuong cong tac toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chieu tinh - ((banh trang) OR (canh tranh)) va phuong cong tac toan ban*.