Perhaps you should try some spelling variations:
thanh trung » thanh tung
khong cong » thong cong, khong cang, chong cong
hieu lang » chieu sang, hieu quang, nhieu tang
trung hua » trung ha, trung hoa, trung cua
hua khong » hoa khong, cua khong, hoac khong
doi hieu » doi chieu, doc hieu, doi hien
cong tac » cong ty
phan cau » phan dau, phan cac, phan lap

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi hieu lang - thanh trung hua khong cong tac ((phan cau) or (phan tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - thanh trung hua khong cong tac ((phan cau) OR (phan tu)).
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - thanh trung hua khong cong tac ((phan cau) or (phan tu))*.