Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
hanh vai » hanh vi, hanh va, hanh tai
vien cac » vien bach, vien dai, vien da
thuc va » thuc vat, thuc dan, thuc day
vai cua » dai cua, hai cua, lai cua
sach ty » sach tu, sach thu, xach tay
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, tuc va, luc va
ang xa » lang xa, mang xa, dang xay

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach ty) OR (sach y)) ang xa hoi. hieu vien cac ((xuc va) OR (thuc va)) hanh vai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ty) OR (sach y)) ang xa hoi. hieu vien cac ((xuc va) OR (thuc va)) hanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) OR (sach y)) ang xa hoi. hieu vien cac ((xuc va) OR (thuc va)) hanh vai cua tre*.