Perhaps you should try some spelling variations:
thong cong » trong cong, tong cong, thong thong
hieu lang » chieu sang, hieu quang, nhieu tang
ganh nang » anh nang, nganh nong, van nang
cua thong » cua thuong, cua khong, cua tong
doi hieu » doi chieu, doc hieu, doi hien
anh dang » anh dong, anh dung, anh bang
cong tac » cong ty
tac phan » tac pham, tai phan, tac phat
phan cau » phan dau, phan cac, phan tu

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 - ((ganh nang) or (anh dang)) cua thong cong tac phan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - ((ganh nang) OR (anh dang)) cua thong cong tac phan cau.
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - ((ganh nang) or (anh dang)) cua thong cong tac phan cau*.