Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
hieu lang » chieu sang, hieu quang, nhieu tang
dang cong » dung cong
doc hieu » toc thieu, hoc thieu, hoc hien
trinh va » trinh van, trinh vat, trinh ve
cong tan » cong tac, cong san, cong thanh
toan cau » toan cao, toan tap, toan tai
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: doc hieu lang - hanh trinh va dang cong tan ((toan cau) or (((toan ban) or (van ban))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu lang - hanh trinh va dang cong tan ((toan cau) OR (((toan ban) OR (van ban)))).
• Adding a wildcard symbol may retrieve word variants: doc hieu lang - hanh trinh va dang cong tan ((toan cau) or (((toan ban) or (van ban))))*.