Perhaps you should try some spelling variations:
chiet tach » chieu sach
hanh trinh » canh tranh, hanh chinh
hoc chiet » hoc thiet, hoc nhiet, hoc hien
trinh cua » tinh cua, trinh luat, trinh quan
vuong dan » tuong dan, xuong dan, vuong dao
cua hung » cua nhung, cua chung, cua huong
toan cau » toan cao, toan tap, toan tai
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc chiet tach - hanh trinh cua hung ((vuong dan) OR (huong dan)) ((toan cau) or (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc chiet tach - hanh trinh cua hung ((vuong dan) OR (huong dan)) ((toan cau) OR (toan ban))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc chiet tach - hanh trinh cua hung ((vuong dan) OR (huong dan)) ((toan cau) or (toan ban))*".