Perhaps you should try some spelling variations:
cong san » cong tac
su triet » su viet, su tien, ve triet
va hanh » van hanh, va thanh, va danh
cac luc » cau luc, coc luc, cac nuoc
hieu va » lieu va, hieu qua
cuu tre » cua tre, cau tren, cau treo
san ky » sang ky, van ky, dan ky
luc va » duc va, tuc va, loc va
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: cong san ky nang ((5 hoi) or (o hoi)). hieu va cac luc va hanh vi ((su triet) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: cong san ky nang ((5 hoi) OR (o hoi)). hieu va cac luc va hanh vi ((su triet) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: cong san ky nang ((5 hoi) or (o hoi)). hieu va cac luc va hanh vi ((su triet) or (cuu tre))*.