Perhaps you should try some spelling variations:
tu sach » thu sach, te sach, tu cach
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
cac tuc » cac toc, cac tu, cac tac
va danh » va dinh, va dan, va hanh
danh co » danh cho, doanh co, anh co
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
tuc va » thuc va, truc va, tuc xa
co cua » con cua, ca cua, cong cua

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) OR (su sach)) y nang ((le hoi) or (ma hoa)). hieu va cac tuc va danh co cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) y nang ((le hoi) OR (ma hoa)). hieu va cac tuc va danh co cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (su sach)) y nang ((le hoi) or (ma hoa)). hieu va cac tuc va danh co cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (su sach)) y nang ((le hoi) or (ma hoa)). hieu va cac tuc va danh co cua tre*.