Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
cac truc » cau truc, cac tru, cac trung
truc va » thuc va, thuc vat, trung va
vu nang » vuc nang, va nang, vu dang
danh ca » dan ca, doanh cua, danh cho
va danh » va dinh, va dan, va hanh
hieu va » lieu va, hieu qua
ca cua » co cua
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) OR (toc sach)) vu nang ((le hoi) or (ma hoa)). hieu va cac truc va danh ca cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) vu nang ((le hoi) OR (ma hoa)). hieu va cac truc va danh ca cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) vu nang ((le hoi) or (ma hoa)). hieu va cac truc va danh ca cua te".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) vu nang ((le hoi) or (ma hoa)). hieu va cac truc va danh ca cua te*.