There are two books you can get, Depending on which the dealer carries, One is called, as best I recall: The RV BOOK, The other: The RV Owner's Handbook.
Both are "Generic" owner's manuals... however how much manual do you need for 4 walls, A floor and a ceiling? I mean that's about all there is to the RV manual.
Now your Microwave, Sink, Doors, Awnings, Windows, Converter and a long list of other things (Toilet) were not made by the company that made the RV and those devices, once you determine the make and model, You can download the manual from the manufacturer's customer support web page.
NOTE: Sometimes the make is smoked.. For example The Microwave in my RV has a well known RV accessory company name on the outside.. But the ID tag says it's a piece of Lousy Goods made by LG (that means lousy goods right,,, Well it does in my book) So of course I had to do a bit of engineering and modification in order to make it work.
But the LG manual still applies.