Do you know your worth?
In series of interview, I have seen, many candidates do not want to expose the expected salary. Most of them said, provide me as per the company rule. And they have no idea on the company rule. If you have no expectation even in your salary, what will expect the company from you. This shows you have no confidence on you.
You should know your value, your strong points and your weak points. Correct your weak points. Review your self. Get feedback from your friends & families. Develop your habbit to listen negative points of yourself. Decrease negativity that ultimately increases positivity.
Know your worth. Be confident.