Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
sach ty » sach y, sach thu, xach tay
xuc van » duc van, luc van, xuc ban
cua tre » cua te, cuu tre, cua triet
sach tu » sach thu, cach tu, sach uu
va cam » va cham, va cac, va cao
vi cua » vai cua, di cua
o hoi » co hoi, o hoc, o hoa
o hai » co hai, so hai, o lai

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

• Performing a fuzzy search may retrieve terms with similar spellings: te ((sach ty) or (sach tu)) nang ((o hoi) OR (o hai)). lieu va cam xuc van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ty) OR (sach tu)) nang ((o hoi) OR (o hai)). lieu va cam xuc van hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ty) or (sach tu)) nang ((o hoi) OR (o hai)). lieu va cam xuc van hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach ty) or (sach tu)) nang ((o hoi) OR (o hai)). lieu va cam xuc van hanh vi cua tre*.