Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
trinh chat » tinh chat, trinh luat, trinh han
tieu sach » chieu sach, dien sach, te sach
dung cong » dung trong
cong cong » cong dong, trong cong, dang cong
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: theo tieu sach - hanh trinh chat ((dung cong) or (cong cong)) san toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo tieu sach - hanh trinh chat ((dung cong) OR (cong cong)) san toan cau.
• Adding a wildcard symbol may retrieve word variants: theo tieu sach - hanh trinh chat ((dung cong) or (cong cong)) san toan cau*.