There is only a one-in-a-million chance of finding one and you would be disappointed once you found it. Few RV owner manuals have much content about specific features or functions and are always generic to several years & models. You can, however, usually find operator manuals for the appliances, e.g. furnace, water heater, fridge, etc. Identify the brand & model of the appliance and Google i with 'manual' appended and it will probably turn up.
The experienced people here can usually help identify the purpose of switches and valves and fuses, the likley places to find things, and general procedures for operating appliances and such. Feel free to ask questions here. Posting photos of the things you want to learn about helps.