Perhaps you should try some spelling variations:
hien sach » dien sach, kien sach, thien hach
hanh tang » hanh trang, anh tang, hanh mang
tang luan » dung luan
hang cong » hang nong, bang cong, thanh cong
dang cong » dung cong
ban thanh » ban hanh, ban hang
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 hien sach - hanh tang luan ((hang cong) OR (dang cong)) ((dan toan) or (ban thanh)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien sach - hanh tang luan ((hang cong) OR (dang cong)) ((dan toan) OR (ban thanh)) cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien sach - hanh tang luan ((hang cong) OR (dang cong)) ((dan toan) or (ban thanh)) cau*".