No, he's talking about dealer service records. If the car has been taken to the dealer for maintenance, they should be recording what the odometer is at the time of that maintenance.
If the car has been taken to an independent shop for maintenance, then it's more difficult, unless you can find out which shop was used. If the car has been self-maintained by the owner, then good luck. But still ... there is probably a dealer service record somewhere. If the last independently-recorded odometer is more than what it shows now, then you know something shady has happened. If the last independently-recorded odometer is from years before and shows that the car has hardly been driven in that time, then it's questionable but you can't prove it.
Where I live, you have to record the odometer each time you renew the vehicle's license plate - so not more than 2 years.
A lot of it is just due to common sense. A car with (let's say) 200,000 km should have its share of wear on the pedals, steering wheel, paint chips in the front from rocks, perhaps a slightly sandblasted appearance to front-facing lights and windshield, etc. If it looks like 200,000 km of wear but the odometer says 80,000, then something is wrong. You can cover up simple and cheap signs of high mileage (e.g. pedal pads) but covering up ALL of them (paint, windshield, headlights, mirror covers, etc) is expensive ... and to be honest, if someone has renewed all of that and kept the car like new despite high mileage then what does it matter (aside from theoretical resale value) if the real odometer is more than what it says?