Perhaps you should try some spelling variations:
hieu nganh » vien nganh, hiem ngan, nghiep nganh
hieu manh » chieu xanh, dieu hanh, hien hanh
hang cong » dang cong, hang nong, bang cong
tranh va » tranh van, trang va, trinh va
cong san » cong tac
va hang » van hang, va nang, va lang
chon tu » con tu, cho tu, choi tu

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 manh) OR (hieu nganh)) - canh tranh va hang cong san ((chon tu) or (phan tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu manh) OR (hieu nganh)) - canh tranh va hang cong san ((chon tu) OR (phan tu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu manh) OR (hieu nganh)) - canh tranh va hang cong san ((chon tu) or (phan tu))".
• Adding a wildcard symbol may retrieve word variants: doc ((hieu manh) OR (hieu nganh)) - canh tranh va hang cong san ((chon tu) or (phan tu))*.