URBANA - The search is on for two men who robbed another man.   He tried to get away, but they had a gun.  In Crime Watch tonight,  it happened in the 1400-block of South Cottage Grove, Monday July 6th.  Investigators say the victim was walking when two men approached him from behind.  He took off running, but they caught him and pushed him down.  While on the ground, one of the suspects put a gun to the man's head and demanded his money.  They took it and ran off.  Urbana police say both offenders are described as black men between 18 and 25 years old.  Both had short hair and were wearing dark clothing.  The first is about six-feet tall and 150 pounds.  The other is five-feet seven-inches tall and skinny.  If you saw the two men that morning or know anything about this robbery, call Champaign County Crimestoppers at 373-TIPS.  You can also send in a text tip on your cell phone or a web tip .   You don't have to give your name or testify in court and a reward is offered.