Perhaps you should try some spelling variations:
mai khoi » mai khoa, tai khoa, cac khoi
hieu van » hieu va, thien van, lieu va
nhan hoi » nhan hoa, nhan hoc, nhan hop
te sach » toc sach
sach ky » sac ky, sach y, sach ty
dai hoi » dai hoc, dai hai, dai moi
van cau » van dau, van hau, van chat
cau duc » cao duc, cau luc, chu duc
va nhan » van nhan, ca nhan, va phan
hoi cua » hoi chuc
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky nang ((mai khoi) or (dai hoi)). hieu van cau duc va nhan hoi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang ((mai khoi) OR (dai hoi)). hieu van cau duc va nhan hoi cua tre.
• Adding a wildcard symbol may retrieve word variants: te sach ky nang ((mai khoi) or (dai hoi)). hieu van cau duc va nhan hoi cua tre*.