Perhaps you should try some spelling variations:
chiet tach » chieu sach
cua nhung » va nhung
cong hach » cong thanh, cong khanh, trong hach
cong sach » ong sach, song sach, duong sach
anh tang » anh bang, anh dang, anh nang
tang cua » mang cua, hang cua, tang luan
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: theo ((chinh sach) or (chiet tach)) - anh tang cua nhung ((cong hach) OR (cong sach)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((chinh sach) OR (chiet tach)) - anh tang cua nhung ((cong hach) OR (cong sach)) toan cao*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((chinh sach) or (chiet tach)) - anh tang cua nhung ((cong hach) OR (cong sach)) toan cao*".