Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
hanh hai » thanh hai, nhanh hai, hang hai
hai cua » thai cua, dai cua, hoi cua
hieu va » lieu va, hieu qua
va tham » van tham, va cham, va thanh
cua tre » cua te, cuu tre, cua triet
va nang » van nang, da nang, cam nang
xuc va » duc va, tuc va, luc va
loc va » hoc va, luc va
v nang » vu nang, van nang, voi nang
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach ((v nang) OR (va nang)) x hoi. hieu va tham ((xuc va) or (loc va)) hanh hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ((v nang) OR (va nang)) x hoi. hieu va tham ((xuc va) OR (loc va)) hanh hai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach ((v nang) OR (va nang)) x hoi. hieu va tham ((xuc va) or (loc va)) hanh hai cua tre".
• Adding a wildcard symbol may retrieve word variants: thuat sach ((v nang) OR (va nang)) x hoi. hieu va tham ((xuc va) or (loc va)) hanh hai cua tre*.