Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
hanh vai » hanh vi, hanh tai, hanh van
vien cac » vien bach, vien dai, vien da
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
hanh va » hang va, hanh vi
cua tre » cua te, cuu tre, cua triet
lang xa » lang ha, dang xay, lang van
ty lang » tay lang, ty xang, ty hang
xuc va » duc va, luc va, xac va
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: su sach ty lang xa hoi. hieu vien cac ((xuc va) or (tuc va)) ((hanh vai) or (hanh va)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty lang xa hoi. hieu vien cac ((xuc va) OR (tuc va)) ((hanh vai) OR (hanh va)) cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ty lang xa hoi. hieu vien cac ((xuc va) or (tuc va)) ((hanh vai) or (hanh va)) cua tre*.