Perhaps you should try some spelling variations:
su sach » so sach, vu sach
mai hoi » mai khoi, dai hoi, lai hoi
qua ban » cua ban, qua quan
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
ma hoi » xa hoi, ma hoa, me hoi
ban bo » can bo, ban do, ban co
va anh » van anh, va danh, va hanh
anh va » hanh va
va cua » va chua, via cua, ca cua
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: su sach y nang ((ma hoi) or (mai hoi)). hieu qua ban bo va anh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang ((ma hoi) OR (mai hoi)). hieu qua ban bo va anh va cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach y nang ((ma hoi) or (mai hoi)). hieu qua ban bo va anh va cua tre*.