Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
thanh song » thanh cong, thanh son, thanh long
nhung cong » dung cong, thong cong, hang cong
hieu cach » hieu cac, chieu sach, hieu ca
van nhung » van nhuong, va nhung, van hung
song van » hoang van, trong van, duong van
san toan » van toan, manh toan, xuan toan
dan toan » van toan, dan than, manh toan

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu cach) or (thien hach)) - thanh song van nhung cong ((san toan) OR (dan toan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu cach) OR (thien hach)) - thanh song van nhung cong ((san toan) OR (dan toan)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu cach) or (thien hach)) - thanh song van nhung cong ((san toan) OR (dan toan)) cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu cach) or (thien hach)) - thanh song van nhung cong ((san toan) OR (dan toan)) cau*.