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 han » trinh quan
cong cong » trong cong, dang cong
dung cong » dung trong
dang tran » dang thanh, quang tran, hoang tran
tran cau » tran chau, toan cau, ran cau

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 han ((((cong cong) or (dung cong))) or (cong dong)) dang tran cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc chiet tach - hanh trinh han ((((cong cong) OR (dung cong))) OR (cong dong)) dang tran cau.
• Adding a wildcard symbol may retrieve word variants: hoc chiet tach - hanh trinh han ((((cong cong) or (dung cong))) or (cong dong)) dang tran cau*.