moving host

I have a wordpress which is running 4.1 , it works fine.

I have just setup anohter wordpress server ( different domanin name ) , the verstion is also 4.1 , I want to move everything from old server to this new server , just use the new server domain name , the purpose is to make a new site for testing.

I tried copy program and database to new server , but it will use old server domain name .

would advise what can I do ? thanks