Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
su sach » so sach, vu sach
sach tu » sach thu, cach tu, sach ty
cua tre » cua te, cua triet, dua tren
va hanh » van hanh, va danh, ban hanh
cac luc » cau luc, coc luc, cac nuoc
hieu va » lieu va, hieu qua
cuu tre » cau tren, cau treo
ang xa » lang xa, mang xa, dang xay
tu ang » tu lang, tu anc, tu anh

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

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