Perhaps you should try some spelling variations:
thieu sach » thien hach, hieu cach, theo sach
chieu sach » chinh sach, chiet tach, chieu sang
hanh hang » thanh hang, hang hang, hanh han
dong cong » duong cong, dung cong, dang cong
dan phan » doan phan, dan chan, dam phan
van phan » van phong, van thanh, luan phan
va dong » van dong, ha dong, xa dong

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: hoc ((thieu sach) OR (chieu sach)) - hanh hang va dong cong ((dan phan) OR (van phan)) cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sach) or (chieu sach)) - hanh hang va dong cong ((dan phan) OR (van phan)) cau~".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) or (chieu sach)) - hanh hang va dong cong ((dan phan) OR (van phan)) cau*.