How do i get the travel/car reimbursment back on tax break?

The company i am working for told me that all my expenses for travel, mileague etc will be reimburst in a form of tax break.deduciton. I did not get any reimbursment from my company for anything.  I was an outside sales rep and had to travel around alot using my own vehicle and paid for gas.  when i filed for deduction, I had at least $6k in expenses (miles and gas).  I filed my return and my reimbursment amount was not on there.  How will i be able to get reimburstment for the expenses? do i need to file a reimburstment form ( form 1040)?