Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thu sach » tu sach, thuat sach, thu hoach
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
ty nang » ky nang, ty xang, ty hang
hieu va » lieu va, hieu qua
van dai » vanh dai, van dao, van hai
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
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) or (thuoc sach)) ty nang x hoi. hieu va cac nuoc va van dai ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (thuoc sach)) ty nang x hoi. hieu va cac nuoc va van dai ((cua tre) OR (cuu tre))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) or (thuoc sach)) ty nang x hoi. hieu va cac nuoc va van dai ((cua tre) OR (cuu tre))*".