Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
hanh vai » hanh vi, hanh va, hanh tai
vai cua » dai cua, hai cua, lai cua
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
mang xa » lang xa, mang may, dang xay
xang xa » lang xa, ang xa, dang xay
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, tuc va, luc va

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 ((xang xa) or (mang xa)) hoi. hieu vien cac ((xuc va) or (tuc xa)) hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((xang xa) OR (mang xa)) hoi. hieu vien cac ((xuc va) OR (tuc xa)) hanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ty ((xang xa) or (mang xa)) hoi. hieu vien cac ((xuc va) or (tuc xa)) hanh vai cua tre*.