Perhaps you should try some spelling variations:
cach thoi » cac thoi, cach thuc, cach noi
doc sach » hoc sach, toc sach, nuoc sach
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
vai cua » dai cua, hai cua, lai cua
y nang » ky nang, ly nang, v nang
va cam » va cham, va cac, va cao
xuc va » duc va, tuc va, luc va
vi cua » di cua

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

• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach y nang ((xa hoi) OR (cach thoi)). hieu va cam xuc va hanh ((vi cua) OR (vai cua)) triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc sach y nang ((xa hoi) or (cach thoi)). hieu va cam xuc va hanh ((vi cua) OR (vai cua)) triet~".
• Adding a wildcard symbol may retrieve word variants: doc sach y nang ((xa hoi) or (cach thoi)). hieu va cam xuc va hanh ((vi cua) OR (vai cua)) triet*.