Perhaps you should try some spelling variations:
chiet tach » chieu sach
hieu lang » chieu sang, hieu quang, nhieu tang
cong cong » cong dong, dung cong, dang cong
anh dung » anh dong, anh huong, sach dung
dung duc » duong duc, dang duc, dung du
dan than » dan chan, ban than, van than
than cau » toan cau, phan cau, than cap

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

• Performing a fuzzy search may retrieve terms with similar spellings: nho ((hieu lang) or (chiet tach)) - anh dung duc ((cong cong) OR (trong cong)) dan than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: nho ((hieu lang) OR (chiet tach)) - anh dung duc ((cong cong) OR (trong cong)) dan than cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "nho ((hieu lang) or (chiet tach)) - anh dung duc ((cong cong) OR (trong cong)) dan than cau".
• Adding a wildcard symbol may retrieve word variants: nho ((hieu lang) or (chiet tach)) - anh dung duc ((cong cong) OR (trong cong)) dan than cau*.