Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
cham xuc » cam xuc, chat xuc, cham soc
va hanh » van hanh, va thanh, va danh
hieu va » lieu va, hieu qua
va cham » va chat, va tham
xuc va » duc va, tuc va, luc va
vi dua » vi du, vi lua
vi dum » vi du
x hoi » xa hoi, o hoi, x ho

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

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