Perhaps you should try some spelling variations:
nhung phuong » dung phuong, nhu phuong, truong phuong
theo chieu » theo tieu, theo chu, thi chieu
hanh duong » thanh duong, khanh duong, hanh dong
ho chieu » hoc thieu, doi chieu, mot chieu
duong va » duong van, dung va, luong va
dan toan » dan than, manh toan, xuan toan
van toan » van tuan, van tan, van thanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((ho chieu) or (theo chieu)) sach - hanh duong va nhung phuong ((dan toan) OR (van toan)) tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (theo chieu)) sach - hanh duong va nhung phuong ((dan toan) OR (van toan)) tap*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) or (theo chieu)) sach - hanh duong va nhung phuong ((dan toan) OR (van toan)) tap*".