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, v nang
hanh ca » hanh cac, hanh cat, hanh cua
vu dang » su dang, vu quang, cua dang
va hanh » van hanh, va thanh, va danh
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: toc sach ((vu nang) or (vu dang)) ((le hoi) or (ma hoa)). hieu va cac truc va hanh ca cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((vu nang) OR (vu dang)) ((le hoi) OR (ma hoa)). hieu va cac truc va hanh ca cua te.
• Adding a wildcard symbol may retrieve word variants: toc sach ((vu nang) or (vu dang)) ((le hoi) or (ma hoa)). hieu va cac truc va hanh ca cua te*.