Perhaps you should try some spelling variations:
nhung phuong » dung phuong, nhu phuong, truong phuong
theo chieu » theo tieu, theo chu, thi chieu
thanh tung » thanh cong
dung chung » dung cong, dung ung, dung trung
ho chieu » hoc thieu, doi chieu, mot chieu
tung cua » trung cua, tuong cua, dung cua
bac toan » bai toan, bao toan, hach 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: ((ho chieu) OR (theo chieu)) sach - thanh tung cua ((nhung phuong) or (dung chung)) bac toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (theo chieu)) sach - thanh tung cua ((nhung phuong) OR (dung chung)) bac toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) OR (theo chieu)) sach - thanh tung cua ((nhung phuong) or (dung chung)) bac toan ban".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) OR (theo chieu)) sach - thanh tung cua ((nhung phuong) or (dung chung)) bac toan ban*.