Perhaps you should try some spelling variations:
tap hanh » tap thanh, tap hinh, tap danh
cao hoi » cau hoi, cao hoc, tao hoi
hieu va » lieu va, hieu qua
cac toi » cac thoi
toi tap » toi gap, toan tap, tong tap
hanh va » hang va, hanh vi
cua tre » cua te, cuu tre, cua triet
vu san » va san, vu ban
tu ban » thu ban, te ban
co hoi » co hoc, co loi
va cua » va chua, via cua, ca 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: ((vu san) OR (tu ban)) ky nang ((cao hoi) OR (co hoi)). hieu va cac toi tap hanh va cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((vu san) or (tu ban)) ky nang ((cao hoi) OR (co hoi)). hieu va cac toi tap hanh va cua tre~".
• Adding a wildcard symbol may retrieve word variants: ((vu san) or (tu ban)) ky nang ((cao hoi) OR (co hoi)). hieu va cac toi tap hanh va cua tre*.