Perhaps you should try some spelling variations:
thieu nien » thien nhien
hieu vien » hieu hien, hieu viec, hieu tieng
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
cac tu » cac thu, cach tu, cac du
ca dan » cac dan, ca dao
dan va » doan va, dan ca, ban va
va cua » va chua, via cua, ca cua
tu ca » tu cua, tu can, tu cay

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu cac ky nang xa hoi. ((hieu vien) OR (thieu nien)) cac tu ca dan va cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ky nang xa hoi. ((hieu vien) OR (thieu nien)) cac tu ca dan va cua tre".
• Adding a wildcard symbol may retrieve word variants: tu cac ky nang xa hoi. ((hieu vien) OR (thieu nien)) cac tu ca dan va cua tre*.