Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
sach tu » sach thu, cach tu, sach ty
tu nang » tru nang, tu nong, tu nano
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
va cham » va chat, va tham
tuc van » thuc van, truc van, tuc va
truc va » thuc va, thuc vat, trung va
hang vi » hang va, hanh vi, hang di
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach tu nang xa hoi. hieu va cham ((tuc van) or (truc va)) hang vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach tu nang xa hoi. hieu va cham ((tuc van) OR (truc va)) hang vi cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach tu nang xa hoi. hieu va cham ((tuc van) or (truc va)) hang vi cua tre*.