Why do you think you should get it all back? Your refund is based on many factors including your tax bracket, your filing status, the amount withheld by your employer and the amount of your tax liability. You only get back the amount of the difference between the amount withheld and the tax you are required to pay the IRS for your situation.
If everyone got it all back where would the government get money?
Do make sure you entered everything completely and correctly. Do not e-file until ALL of your information has been entered on the SAME Form 1040.