Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu xanh
chieu sang » chieu xanh, hieu lang, nhieu tang
hanh trinh » canh tranh, hanh chinh
trinh va » trinh van, trinh vat, trinh ve
cong tan » cong tac, cong thanh, cong ty
cong san » cong tac
toan cao » toan ban, toan tap

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sach) OR (chieu sang)) - hanh trinh va nhung ((cong tan) OR (cong san)) toan cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((chieu sach) OR (chieu sang)) - hanh trinh va nhung ((cong tan) or (cong san)) toan cao~".
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sach) OR (chieu sang)) - hanh trinh va nhung ((cong tan) or (cong san)) toan cao*.