Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
hanh trinh » canh tranh, hanh chinh
nhung cong » dung cong, thong cong, hang cong
trinh cua » tinh cua, trinh luat, trinh quan
cua nhung » va nhung
van toan » van tuan, van tan, van thanh
dan toan » dan than, manh toan, xuan toan

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc thieu sach - hanh trinh cua nhung cong ((van toan) or (dan toan)) ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc thieu sach - hanh trinh cua nhung cong ((van toan) OR (dan toan)) ban.
• Adding a wildcard symbol may retrieve word variants: toc thieu sach - hanh trinh cua nhung cong ((van toan) or (dan toan)) ban*.