Q: A/C warm air and compressor comes on

The compressor comes on when I turn on the air conditioning and the internal blower fan goes on high. But the condenser will not come on. The air from the A/C is never very cold. I have a friend who has a repair shop and we evacuated the system, plus used his machine to re-pressurize and refill it. That was all he could do at that time. In my thinking, it might be a relay problem. While under the hood, I looked at the relays near the fuse panel, however they are not labeled. Do you think it’s a relay problem and if so, could you tell me which one it is or where I can get a diagram? Thank you.