Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
te sach » toc sach
va hanh » van hanh, va danh, ban hanh
sach ky » sac ky, sach y, sach ty
cam tuc » cam xuc, cam tu, nam thuc
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
ve cam » ve cham, ve cac, va cam
vi cua » vai cua, di cua
o hoi » co hoi, o hoc, o hai
x hoi » xa hoi, x ho, 5 hoi

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 ky nang ((x hoi) or (o hoi)). hieu ve cam tuc ((va hanh) OR (va thanh)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang ((x hoi) OR (o hoi)). hieu ve cam tuc ((va hanh) OR (va thanh)) vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang ((x hoi) or (o hoi)). hieu ve cam tuc ((va hanh) OR (va thanh)) vi cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang ((x hoi) or (o hoi)). hieu ve cam tuc ((va hanh) OR (va thanh)) vi cua tre*.