Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
hieu va » lieu va
va hanh » van hanh, va danh, ban hanh
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky lang xa hoi. ((hieu va) OR (hieu qua)) cam xuc ((va hanh) or (va thanh)) dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky lang xa hoi. ((hieu va) OR (hieu qua)) cam xuc ((va hanh) OR (va thanh)) dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky lang xa hoi. ((hieu va) OR (hieu qua)) cam xuc ((va hanh) or (va thanh)) dai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky lang xa hoi. ((hieu va) OR (hieu qua)) cam xuc ((va hanh) or (va thanh)) dai cua tre*.