Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
hanh trinh » canh tranh
nhung cong » dung cong, thong cong, hang cong
hoc thieu » toc thieu, hoc hien
cong san » cong tac
san toan » van toan, dan toan, manh toan
toan cau » 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: hoc thieu sach - ((hanh trinh) or (hanh chinh)) va nhung cong san toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sach - ((hanh trinh) OR (hanh chinh)) va nhung cong san toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc thieu sach - ((hanh trinh) or (hanh chinh)) va nhung cong san toan cau*.