Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
tu sach » su sach, te sach, tu cach
nang xa » nang x, lang xa, nang ma
hieu va » hieu qua
va hanh » van hanh, va thanh, va danh
hanh va » hang va, hanh vi
cuu tre » cua tre, cau tren, cau treo
y nang » ky nang, ly nang, v nang
va cuu » va cau, va chu, va huu

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