Perhaps you should try some spelling variations:
canh trinh » canh tranh, hanh trinh, canh tinh
hang cong » dang cong, hang nong, bang cong
hien anh » hien hanh, thien anh, dien anh
dien dan » hien dai, vien dai, gian dan
trinh va » trinh van, trinh vat, trinh ve
cong san » cong tac
san chan » san chang, dan chan, san chay
chan cau » phan cau, can cau, chinh cau
va hang » van hang, 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: hoc ((hien anh) or (dien dan)) - canh trinh va hang cong san chan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien anh) OR (dien dan)) - canh trinh va hang cong san chan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((hien anh) or (dien dan)) - canh trinh va hang cong san chan cau*.