Perhaps you should try some spelling variations:
thanh trong » thanh trung, tranh trong, hanh trong
trong thap » trong thai, trong phap, trong thuat
thap thong » phap thong, khap thong, thap trong
cong thanh » dong thanh, cong trinh, truong thanh
hieu lang » chieu sang, hieu quang, nhieu tang
hoi hieu » hoi phieu, hoi tieu, moi hieu
cong tan » cong tac, cong san, cong ty
toan cau » toan cao, toan tap, toan tai
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: hoi hieu lang - thanh trong thap thong ((cong tan) or (cong thanh)) ((toan cau) OR (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoi hieu lang - thanh trong thap thong ((cong tan) OR (cong thanh)) ((toan cau) OR (toan ban)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoi hieu lang - thanh trong thap thong ((cong tan) or (cong thanh)) ((toan cau) OR (toan ban))".
• Adding a wildcard symbol may retrieve word variants: hoi hieu lang - thanh trong thap thong ((cong tan) or (cong thanh)) ((toan cau) OR (toan ban))*.