Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
va thanh » gia thanh, ban thanh, va tinh
thanh va » thanh van, hanh va, thanh ha
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu va » hieu qua
cuu tre » cau tren, cau treo
cua tre » cua te, cua triet, dua tren

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 ky nang xa hoi. ((hieu va) or (lieu va)) giao duc va thanh va ((cuu tre) OR (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang xa hoi. ((hieu va) OR (lieu va)) giao duc va thanh va ((cuu tre) OR (cua tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang xa hoi. ((hieu va) or (lieu va)) giao duc va thanh va ((cuu tre) OR (cua tre))".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang xa hoi. ((hieu va) or (lieu va)) giao duc va thanh va ((cuu tre) OR (cua tre))*.