Perhaps you should try some spelling variations:
cac nuoc » hoc nuoc, dat nuoc, cua nuoc
cap nuoc » dat nuoc
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
van dai » vanh dai, van dao, van hai
cua tre » cua te, cuu tre, cua triet
x hoi » xa hoi, o hoi, x ho

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang x hoi. hieu qua ((cac nuoc) OR (cap nuoc)) va van dai cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang x hoi. hieu qua ((cac nuoc) OR (cap nuoc)) va van dai cua tre*.