Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
ty nang » ty xang, ty hang, ly nang
hieu va » lieu va, hieu qua
van dai » vanh dai, van dao, van hai
cua tre » cuu tre, cua triet, dua tren
cua te » cua tu
x hoi » xa hoi, o hoi, x ho

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 ((ty nang) or (ky nang)) x hoi. hieu va cac nuoc va van dai ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((ty nang) OR (ky nang)) x hoi. hieu va cac nuoc va van dai ((cua tre) OR (cua te))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((ty nang) or (ky nang)) x hoi. hieu va cac nuoc va van dai ((cua tre) OR (cua te))*".