Perhaps you should try some spelling variations:
thanh tung » thanh cong
hieu lang » chieu sang, hieu quang, nhieu tang
dap luong » dai luong, da luong, do luong
doi hieu » doi chieu, doc hieu, doi hien
tung dap » tung dan, trung dai, tuong dan
cong tac » cong ty
toan cau » toan ban, toan tap, toan tai
toan cao » toan ban, toan tap

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 tung dap luong ((cong san) or (cong tac)) ((toan cau) or (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - thanh tung dap luong ((cong san) OR (cong tac)) ((toan cau) OR (toan cao)).
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - thanh tung dap luong ((cong san) or (cong tac)) ((toan cau) or (toan cao))*.