Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
sach tu » sach thu, sach ty, sach uu
duc ban » duc tan, duc van, dua ban
xuc ban » cuc ban, quoc ban, xuat ban
van cam » van nam, van lam, van cau
cach tu » cach thuc
cua tre » cua te, cuu tre, cua triet
nang o » nang co, nang ho, nang ro
vi cua » vai cua, di cua
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach tu) or (cach tu)) nang o hoi. hieu van cam ((xuc ban) or (duc ban)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach tu) OR (cach tu)) nang o hoi. hieu van cam ((xuc ban) OR (duc ban)) hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach tu) or (cach tu)) nang o hoi. hieu van cam ((xuc ban) or (duc ban)) hanh vi cua tre*.