Perhaps you should try some spelling variations:
hieu vien » hieu viec, thieu nien, hieu tieng
hieu hien » bieu hien, dieu hien, chieu chien
hanh dai » hanh tai, hanh dao, vanh dai
cac tuc » cac toc, cac tu, cac tac
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
tu san » thu san, tu ban, vu san
tu can » tu ban, tu cac, thu canh
tuc va » thuc va, truc va, tuc xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu san) OR (tu can)) ky nang x ho. ((hieu vien) or (hieu hien)) cac tuc va hanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu san) OR (tu can)) ky nang x ho. ((hieu vien) OR (hieu hien)) cac tuc va hanh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu san) OR (tu can)) ky nang x ho. ((hieu vien) or (hieu hien)) cac tuc va hanh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu san) OR (tu can)) ky nang x ho. ((hieu vien) or (hieu hien)) cac tuc va hanh dai cua tre*.