Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
chieu lang » chieu sang, chi lang, chieu xanh
hieu lang » chieu sang, hieu quang, nhieu tang
dang cong » dung cong
trinh va » trinh van, trinh vat, trinh ve
cong tan » cong tac, cong san, cong thanh
toan cau » toan ban, toan tap, toan tai
toan cao » toan ban, toan tap
va dang » van dang, va nang, va lang

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

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