We keep our travel trailer in a seasonal camp ground and I would like to check the pole where the trailer is plugged in . We pay a extra premium to have 30 amps and I do not think we are getting it . You see when we are there the air conditioning doesn't work very good in the day time when everyone is using their A/C. But at night after everyone shuts there A/C off our starts working good like. I know for a fact that he has more than one trailer per breaker , its more like 4 or 5.

...........We pay a extra premium to have 30 amps and i do not think we are getting it ...........................I know for a fact that he has more than one trailer per breaker , its more like 4 or 5.
Then you are not getting a 30A circuit.
I would check the voltage at your receptacles when the A/C is not working well. If it is below 110v or so you are in a low voltage condition, most likely due to voltage drop. This could be for several reasons but it is a symptom of something not right.

If you are having that problem some of your other neighbors may be having the same problem due to voltage drop through your feed wires.