If you want to carry out maintenance for your Sym Mio 50 then it will always be a good plan to have access to a Workshop Manual to keep just for a reference in case you need to know techniques to remove a specific component like the Drive Shaft and fit it again accordingly.
Sym Mio 50 Workshop Manuals provide you with detailed diagnostic info for your vehicle so if something is wrong it will help you find out what the situation is and the way to resolve it. You can then evaluate if you can do this by yourself or in case the job is too big you could book your Mio 50 in with a decent mechanic.
Sym Mio 50 manual