Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
nhieu tang » chieu sang, hieu lang, nhiet nang
thanh tung » thanh cong
phung cong » nhung cong, phong cong, nhung chong
cam phung » cam hung, cam nhung, nam phuong
tung cam » dung cam, trung cap, tung pham
van toan » van tuan, van thanh, manh toan
van tan » van tuan, van ban, van tai

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) OR (nhieu tang)) - thanh tung cam phung cong ((van toan) OR (van tan)) cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi ((chieu sach) or (nhieu tang)) - thanh tung cam phung cong ((van toan) OR (van tan)) cao~".
• Adding a wildcard symbol may retrieve word variants: doi ((chieu sach) or (nhieu tang)) - thanh tung cam phung cong ((van toan) OR (van tan)) cao*.