Little cute blackie don't know her own name!

Little Blackie been one of our family member since 15th August 2009. She was born in 28th April 2009 so will be 4 months old soon!.. At first when we bought her back, she's so cute and obedient that she never poo poo or pee outside her 'home'. So, unluckily, now she turn her nature behavior of being naughty and not listening to order. Even when we call her "Blackie, Blackie..." she seldom turn up to us. Before this we thought maybe she's new to this home and this name, so she may not recognize our voice and even her own name. But now it's about a month since she stay here, yet she never really actually one time respond to our call. Just some time she just coincidently turn over and run to us, we are all so happy and just assume that she really know her own name.. However, take care of a dog really tired and spend a lot of money. For vaccine, medicine, foods, toys, accessories, and also the cost of the time needed to pay attenlion to her. Like taking care of a newborn baby. All energy, attention and commitment are focus on her. Hopefully she will understand that she's now one part of the family and at least response to our call whenever we call for her..