Perhaps you should try some spelling variations:
te sach » toc sach
va danh » va dinh, va dan, dia danh
va hanh » van hanh, va thanh, ban hanh
cam tuc » cam xuc, cam tu, nam thuc
sach ty » sach y, sach tu, sach thu
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
ty nang » ky nang, ty xang, ty hang
vi cua » vai cua, di cua
ve cam » ve cham, ve cac, va cam
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: te sach ty nang ((xa hoi) or (o hoi)). hieu ve cam tuc ((va hanh) OR (va danh)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty nang ((xa hoi) OR (o hoi)). hieu ve cam tuc ((va hanh) OR (va danh)) vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty nang ((xa hoi) or (o hoi)). hieu ve cam tuc ((va hanh) OR (va danh)) vi cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach ty nang ((xa hoi) or (o hoi)). hieu ve cam tuc ((va hanh) OR (va danh)) vi cua tre*.