Perhaps you should try some spelling variations:
nhung phuong » dung phuong, nhu phuong, truong phuong
chieu sach » chinh sach, chiet tach, chieu sang
thanh tung » thanh cong
doi chieu » doc hieu, doi chi, ho chieu
van toan » van tan, van thanh, manh toan
van tuan » van quan, van ban, anh tuan

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

• If you are trying to use Boolean operators, they must be ALL CAPS: doi chieu sach - ((thanh trung) OR (thanh tung)) va nhung phuong ((van toan) OR (van tuan)) ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi chieu sach - ((thanh trung) or (thanh tung)) va nhung phuong ((van toan) OR (van tuan)) ban~".
• Adding a wildcard symbol may retrieve word variants: doi chieu sach - ((thanh trung) or (thanh tung)) va nhung phuong ((van toan) OR (van tuan)) ban*.