The majority of the RV manufacturers will put together a packet of manuals for each of the devices and appliances in your RV, along with a rather generic manual on the RV itself. That manual usually covers several models and is not specific to your model.
If you are buying used, you are at the mercy of the previous owners to provide these manuals when they sell.
If you did not get paper manuals, they are pretty readily available on the manufacture's website.
So, if for instance, you want a manual for your furnace, you find the model of it on the serial number plate, and go to the manufactures website to download it
Here is a link to the 2015 Crossroads manual, that may be as close as you are going to get:
https://www.crossroadsrv.com/media/3...ers-manual.pdf