Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hanh tai » thanh tai, hang tai, han tai
hieu va » lieu va
tai cua » thai cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
xuc va » duc va, tuc va, xac va
luc va » duc va, tuc va, loc va

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

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