Perhaps you should try some spelling variations:
truong quan » trong quan, thong quan, truong van
luong quan » thong quan, duong qua
nhung cong » dung cong, thong cong, hang cong
hieu cach » chieu sach, hieu ca, biet cach
hieu cac » hieu luc, hieu va, hieu van
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
toan cau » 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: doc ((hieu cach) or (hieu cac)) - thanh ((truong quan) OR (luong quan)) nhung cong dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu cach) OR (hieu cac)) - thanh ((truong quan) OR (luong quan)) nhung cong dan toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu cach) or (hieu cac)) - thanh ((truong quan) OR (luong quan)) nhung cong dan toan cau".
• Adding a wildcard symbol may retrieve word variants: doc ((hieu cach) or (hieu cac)) - thanh ((truong quan) OR (luong quan)) nhung cong dan toan cau*.