Perhaps you should try some spelling variations:
hanh via » hanh vi, hanh va, anh va
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
cao hoi » cau hoi, cao hoc, cao hon
tao hoi » tao khoi, tao boi, tay hoi
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
via cua » gia cua, gian cua, giau cua
cua tre » cua te, cuu tre, cua triet
co hoi » co hoc, co loi
va bao » va bai
bao bo » bac bo, ban bo, nao bo
bo va » bao va, do va, so va

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ky nang ((((cao hoi) or (tao hoi))) or (co hoi)). hieu va bao bo va hanh via cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky nang ((((cao hoi) OR (tao hoi))) OR (co hoi)). hieu va bao bo va hanh via cua tre.
• Adding a wildcard symbol may retrieve word variants: vu sach ky nang ((((cao hoi) or (tao hoi))) or (co hoi)). hieu va bao bo va hanh via cua tre*.