Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
va triet » va thiet, va trien, ve triet
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
cac tuc » cac toc, cac tu, cac tac
tuc van » thuc van, truc van, tuc va
van cac » van hac, van cau, van bac
sai ky » sac ky
co hoi » co hoc, co loi
su sai » su tai, su hai, su dai
o hoi » o hoc, o hai, o hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sai ky nang ((o hoi) OR (co hoi)). hieu van cac tuc van hanh vi ((va triet) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sai ky nang ((o hoi) OR (co hoi)). hieu van cac tuc van hanh vi ((va triet) OR (su triet))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sai ky nang ((o hoi) OR (co hoi)). hieu van cac tuc van hanh vi ((va triet) or (su triet))*".