Perhaps you should try some spelling variations:
viet sach » viet anh, dien sach, viet tech
tranh cua » doanh cua, manh cua
cua nhung » va nhung
dong kinh » trong kinh
dai viet » mai viet, dao viet, tai viet
dung tin » dong tin, luong tin, dung tren
toan cau » toan cao, toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: dai viet sach - canh tranh cua nhung ((dung tin) or (dong kinh)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: dai viet sach - canh tranh cua nhung ((dung tin) OR (dong kinh)) toan cau.
• Adding a wildcard symbol may retrieve word variants: dai viet sach - canh tranh cua nhung ((dung tin) or (dong kinh)) toan cau*.