Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
sach ty » sach y, sach tu, sach thu
van dai » vanh dai, van dao, van hai
cam tuc » cam xuc, cam tu, dam thuc
tu sach » thu sach, su sach, te sach
cua tre » cua te, cuu tre, cua triet
ty nang » ky nang, ty xang, ty hang
so hai » son hai, su hai, so ha
o hai » co hai, o lai, _ hai

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: tu sach ty nang ((o hai) OR (so hai)). hieu qua ((cam tuc) OR (nam thuc)) va van dai cua tre~.
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang ((o hai) or (so hai)). hieu qua ((cam tuc) or (nam thuc)) va van dai cua tre*.