Perhaps you should try some spelling variations:
hanh vai » hanh va, hanh tai, hanh van
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
van lam » van nam
long ha » dong ha, cong ha, dong hoa
cua tre » cua te, cuu tre, cua triet
lam lo » nam lo, lam co, cam lo
lo van » le van, vo van, so van

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((long ha) OR (van xay)) hoi. hieu van lam lo van ((hanh vai) OR (hanh vi)) cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky ((long ha) or (van xay)) hoi. hieu van lam lo van ((hanh vai) OR (hanh vi)) cua tre~".
• Adding a wildcard symbol may retrieve word variants: su sach ky ((long ha) or (van xay)) hoi. hieu van lam lo van ((hanh vai) OR (hanh vi)) cua tre*.