Perhaps you should try some spelling variations:
thong cong » trong cong, tong cong, thong thong
theo hieu » theo chieu, theo tieu, thien hieu
hieu lang » chieu sang, hieu quang, nhieu tang
cua thong » cua thuong, cua khong, cua tong
canh ban » can ban, doanh ban, tranh ban
canh dan » sanh dan, thanh dan, cac dan
canh van » anh van, can van, cach van
cong san » cong tac
san toan » van toan, dan toan, manh toan
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: theo hieu lang - ((((canh ban) OR (canh dan))) or (canh van)) cua thong cong san toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo hieu lang - ((((canh ban) OR (canh dan))) OR (canh van)) cua thong cong san toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo hieu lang - ((((canh ban) OR (canh dan))) or (canh van)) cua thong cong san toan ban".
• Adding a wildcard symbol may retrieve word variants: theo hieu lang - ((((canh ban) OR (canh dan))) or (canh van)) cua thong cong san toan ban*.