How to unlock the phone?

Last week I buy a cell phone from China company. Before I paid, I have confirmed that this phone can work in my country from customer service. Once I received it, I am so excited. But once a while, I am so sad. It does not work. I have asked company for solution. But he said I must return it for test. And I will get help. So I hope some one can help me to tell me any solutions. The shipping cost is so high.

The cell phone can not read my SIM card. It can not find network service. I just can give emergent call. What is problem? I think it needs to decode the phone. And then I can use it. Is it right?