Perhaps you should try some spelling variations:
cong thanh » dong thanh, cong trinh, cong tan
hieu quang » thieu quang, hieu quan, hieu qua
thanh toan » thanh hoa, thanh san, tinh toan
theo hieu » theo chieu, theo tieu, thien hieu
cua thong » cua thuong, cua khong, suat thong
canh van » anh van, can van, cach van
cua tong » cua cong, cua dong, cua nong
toan ban » van ban
can 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: theo hieu quang - ((can ban) or (canh van)) ((cua thong) OR (cua tong)) cong thanh toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo hieu quang - ((can ban) OR (canh van)) ((cua thong) OR (cua tong)) cong thanh toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo hieu quang - ((can ban) or (canh van)) ((cua thong) OR (cua tong)) cong thanh toan ban".
• Adding a wildcard symbol may retrieve word variants: theo hieu quang - ((can ban) or (canh van)) ((cua thong) OR (cua tong)) cong thanh toan ban*.