Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
thanh va » thanh van, hanh va, thanh ha
hieu ve » hieu va, hieu van
cao duc » dao duc, cao suc, giao duc
luu tre » cuu tre, luy tre
so sac » so sach, so dac
sac ky » cac ky, sai ky
ve cao » va cao, ve bao, ve cac
tru » truc

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sac ky nang ((x ho) or (xa hoi)). hieu ve cao duc va thanh va ((luu tre) OR (luu tru))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sac ky nang ((x ho) OR (xa hoi)). hieu ve cao duc va thanh va ((luu tre) OR (luu tru)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sac ky nang ((x ho) or (xa hoi)). hieu ve cao duc va thanh va ((luu tre) OR (luu tru))".
• Adding a wildcard symbol may retrieve word variants: so sac ky nang ((x ho) or (xa hoi)). hieu ve cao duc va thanh va ((luu tre) OR (luu tru))*.