Perhaps you should try some spelling variations:
hanh tai » thanh tai, hang tai, han tai
hieu van » hieu va, thien van, lieu va
hanh vai » hanh vi, hanh va, hanh van
so sach » so sanh, bo sach, co sach
sach tu » sach thu, cach tu, sach ty
cua tre » cua te, cuu tre, cua triet
van cam » van nam, van lam, van cau
lang xa » lang ha, dang xay, lang van
tu lang » cu lang, tu lanh, xu lang
luc va » duc va, tuc va, loc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach tu lang xa hoi. hieu van cam ((luc va) or (hoc va)) ((hanh vai) or (hanh tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach tu lang xa hoi. hieu van cam ((luc va) OR (hoc va)) ((hanh vai) OR (hanh tai)) cua tre.
• Adding a wildcard symbol may retrieve word variants: so sach tu lang xa hoi. hieu van cam ((luc va) or (hoc va)) ((hanh vai) or (hanh tai)) cua tre*.