Perhaps you should try some spelling variations:
viet duc » viet dung
viet dua » viet duy, viet qua, viet da
cham xuc » cam xuc, chat xuc, cham soc
toc sach » hoc sach, doc sach, thuoc sach
hieu va » lieu va, hieu qua
va cham » va chat, va tham
va dinh » van dinh, va kinh, va tinh
xuc va » duc va, tuc va, luc va
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 dinh ((viet dua) OR (viet duc)) 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 dinh ((viet dua) OR (viet duc)) tren~".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) ky nang x hoi. hieu va cham xuc va dinh ((viet dua) OR (viet duc)) tren*.