Perhaps you should try some spelling variations:
so sach » so sanh, bo sach, co sach
hieu va » lieu va, hieu qua
cac tac » cac bac, cac dac, cac tai
cac toc » cac toi, cac nuoc, cac thoi
va danh » va dinh, va dan, va hanh
danh ca » dan ca, doanh cua, danh cho
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
ca cua » co cua

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: so sach y nang ((le hoi) OR (ma hoa)). hieu va ((cac tac) OR (cac toc)) va danh ca cua tre~.
• Adding a wildcard symbol may retrieve word variants: so sach y nang ((le hoi) or (ma hoa)). hieu va ((cac tac) or (cac toc)) va danh ca cua tre*.