Perhaps you should try some spelling variations:
thanh dieu » thanh lieu, than dieu, hanh dieu
ban thanh » ban hanh, ban hang
dieu cua » dieu tra
dong hoc » dong co, dong luc
so sach » so sanh, co sach, hoc sach
ve chat » va chat, van chat
vuc ban » vu ban, duc ban, cuc ban
vu chat » va chat, du chat, vu cham
hoc hoi » hoc khoi, hoc hoa, hoc noi
ty dong » tay dong, tu dong, ly dong
bo sach » co sach, hoc sach
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: ((so sach) or (bo sach)) ty dong hoc hoi. hieu ((vu chat) or (ve chat)) vuc ban thanh dieu cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (bo sach)) ty dong hoc hoi. hieu ((vu chat) OR (ve chat)) vuc ban thanh dieu cua tre.
• Adding a wildcard symbol may retrieve word variants: ((so sach) or (bo sach)) ty dong hoc hoi. hieu ((vu chat) or (ve chat)) vuc ban thanh dieu cua tre*.