Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu va » lieu va, hieu qua
cac tac » cac toc, cac bac, cac dac
va hanh » van hanh, va thanh, va danh
hanh ca » hanh cac, hanh cat, hanh cua
cuu tre » cua tre, cau tren, cau treo
y nang » ky nang, ly nang, v nang
me hoi » le hoi
tac va » tac da, tac xa, tuc va
ca cuu » cap cuu, cua cuu, ca cua

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 ((me hoi) or (ma hoa)). hieu va cac tac va hanh ca cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y nang ((me hoi) OR (ma hoa)). hieu va cac tac va hanh ca cuu tre.
• Adding a wildcard symbol may retrieve word variants: thu sach y nang ((me hoi) or (ma hoa)). hieu va cac tac va hanh ca cuu tre*.