Perhaps you should try some spelling variations:
hanh phan » thanh phan, anh phan, hanh nhan
hanh han » hanh nhan, hanh san, anh han
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
duc ban » duc tan, duc van, dua ban
van lam » van nam
lam duc » lam duoc, pham duc, nam duoc
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: su sach ky nang ((x hoi) or (o hoi)). hieu van lam duc ban ((hanh phan) OR (hanh han)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ((x hoi) OR (o hoi)). hieu van lam duc ban ((hanh phan) OR (hanh han)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang ((x hoi) or (o hoi)). hieu van lam duc ban ((hanh phan) OR (hanh han)) cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ((x hoi) or (o hoi)). hieu van lam duc ban ((hanh phan) OR (hanh han)) cua tre*.