Perhaps you should try some spelling variations:
thuong dong » phuong dong, tuong dong, chuong dong
hieu lang » chieu sang, hieu quang, nhieu tang
hoc hieu » hoc thieu, hoc hien, doc hieu
dong tan » duong tan, dong tai, dong san
than cau » toan cau, than cap, thanh chau
phan cau » phan dau, phan cac, phan tu
cong va » dong va, cong ha, cong tac

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hieu lang - thanh cong va thuong dong tan ((than cau) or (phan cau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu lang - thanh cong va thuong dong tan ((than cau) OR (phan cau)).
• Adding a wildcard symbol may retrieve word variants: hoc hieu lang - thanh cong va thuong dong tan ((than cau) or (phan cau))*.