Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
nhieu tang » chieu sang, nhiet nang
hieu lang » chieu sang, hieu quang, hieu van
trinh va » trinh van, trinh vat, trinh ve
cong dan » cong tan, huong dan, cong dong
cong san » cong tac
chan cau » phan cau, can cau, chinh cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi ((nhieu tang) or (hieu lang)) - hanh trinh va nhung ((cong dan) OR (cong san)) chan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((nhieu tang) OR (hieu lang)) - hanh trinh va nhung ((cong dan) OR (cong san)) chan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi ((nhieu tang) or (hieu lang)) - hanh trinh va nhung ((cong dan) OR (cong san)) chan cau".
• Adding a wildcard symbol may retrieve word variants: doi ((nhieu tang) or (hieu lang)) - hanh trinh va nhung ((cong dan) OR (cong san)) chan cau*.