Your original post is confusing.
I have tested the breakers and they are good however no voltage to two breaker coming of the bar the breaker connect to.
I assume "of" is off, but this makes no sense, A standard main service panel power comes in to one or two main breakers, is transferred to a bar and tapped off by the other breakers, if there is no voltage on the bar NOTHING 120 volt in the RV will work.
In a SUB panel power comes in straight to the bar, but again breakers tap off it.
If there is no power on the bar, the breakers can not be tested.
That said:
I agree with the folks above who suspect an INVERTER sub panel, either on the inverter or somewhere other than where you main panel is. In fact that would fit your description.
problems I have had (I have a sub panel) include tripped breakers, failed Inverter, and . once,, failed connection.. Some connections epically where solid wire (ROMEX) and stranded wire (The leads from the inverter) meet can fail easily.. (I re-did it with solder the 2nd time).