Perhaps you should try some spelling variations:
tieu sach » chieu sach, te sach, viet sach
dien sach » dien anh
dang cong » dung cong
tranh va » tranh van, trang va, trinh va
dan than » ban than, van than, dan toan
dan chan » dan gian, dan ca, van chat
va dang » van dang, va nang, va lang

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: theo ((tieu sach) OR (dien sach)) - canh tranh va dang cong ((dan than) OR (dan chan)) cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((tieu sach) OR (dien sach)) - canh tranh va dang cong ((dan than) or (dan chan)) cao~".
• Adding a wildcard symbol may retrieve word variants: theo ((tieu sach) OR (dien sach)) - canh tranh va dang cong ((dan than) or (dan chan)) cao*.