Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
danh di » danh du, xanh di, danh dien
duoc va » nuoc va, duc va, duoc ma
tuoc va » thuoc va, nuoc va, tuc va
sach ky » sac ky, sach y, sach ty
vu sach » vu bach, su sach, vu khach
mai hoi » mai khoi, dai hoi, lai hoi
cua tre » cua te, cuu tre, cua triet
ma hoi » xa hoi, ma hoa, me hoi
di cua » dai cua, doi cua, de 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 sach ky nang ((ma hoi) OR (mai hoi)). hieu vien bach ((tuoc va) OR (duoc va)) danh di cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky nang ((ma hoi) OR (mai hoi)). hieu vien bach ((tuoc va) or (duoc va)) danh di cua tre~".
• Adding a wildcard symbol may retrieve word variants: vu sach ky nang ((ma hoi) OR (mai hoi)). hieu vien bach ((tuoc va) or (duoc va)) danh di cua tre*.