Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
va triet » va thiet, ve triet, cua triet
va trien » va truyen, va thiet, va tuyen
nang xa » nang x, lang xa, nang ma
cac tuc » cac toc, cac tu, cac nuoc
cac tac » cac toc, cac bac, cac dac
va hanh » van hanh, va thanh, va danh
su cac » tu cac, su cao, su can

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

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