Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
va thanh » gia thanh, va tinh, le thanh
su sach » so sach, vu sach
nam xuc » cam xuc, nam xua, nam thuc
cua tre » cua te, cuu tre, cua triet
ty nang » ky nang, ty xang, ty hang
sach ty » sach y, sach tu, sach thu
vi cua » vai cua, di cua
va nam » van nam, ha nam, va nay
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: su sach ty nang ((o hoi) or (xa hoi)). lieu va nam xuc ((va thanh) OR (ban thanh)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang ((o hoi) OR (xa hoi)). lieu va nam xuc ((va thanh) OR (ban thanh)) vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty nang ((o hoi) or (xa hoi)). lieu va nam xuc ((va thanh) OR (ban thanh)) vi cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ty nang ((o hoi) or (xa hoi)). lieu va nam xuc ((va thanh) OR (ban thanh)) vi cua tre*.