Expungement of dismissed charges?

I had a battery charge misdimeanor 2 years ago. It got dismissed when I went to court. I have been on unemployment for these past two years, I applied for a job and got denied on my background for a misdimeanor/felony. If it got dismissed then why did it come up? How can I get it expunged or is it always going to be on my record and am I always going to have a problem getting a job? Confused and any information would be appreciated! thank u!