Perhaps you should try some spelling variations:
thuyet sach » thuyet mach, thuyet hach, thuyet xac
hoc thuyet » hoc chuyen
hanh trinh » canh tranh, hanh chinh
trinh xuat » trinh luat, trinh xuan, trich xuat
xuat thong » xuat thuong, suat thong, luat thuong
thong cong » trong cong, tong cong, thong thong
dan than » dan chan, van than, dan toan
ban than » ban thanh, van thanh, ban hang

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thuyet sach - hanh trinh xuat thong cong ((dan than) or (ban than)) man~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thuyet sach - hanh trinh xuat thong cong ((dan than) OR (ban than)) man.
• Adding a wildcard symbol may retrieve word variants: hoc thuyet sach - hanh trinh xuat thong cong ((dan than) or (ban than)) man*.