Perhaps you should try some spelling variations:
bach thuoc » bach tuoc, cach thuc, ban thuoc
thieu vien » thieu nien, thieu bien, thu vien
va thanh » gia thanh, ban thanh, va tinh
hoi cua » hoi chuc
va hanh » van hanh, va danh, ban hanh
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cuu tre, cua triet
o hoi » co hoi, o hoc, o hai
x hoi » xa hoi, x ho, 5 hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ky nang ((x hoi) or (o hoi)). thieu vien bach thuoc ((va hanh) OR (va thanh)) hoi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky nang ((x hoi) OR (o hoi)). thieu vien bach thuoc ((va hanh) OR (va thanh)) hoi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ky nang ((x hoi) or (o hoi)). thieu vien bach thuoc ((va hanh) OR (va thanh)) hoi cua tre".
• Adding a wildcard symbol may retrieve word variants: so sach ky nang ((x hoi) or (o hoi)). thieu vien bach thuoc ((va hanh) OR (va thanh)) hoi cua tre*.