Should I lubricate moving parts of electric dryer? If yes, then how?
Your Dryer manufacturer should have a part number for lubricants that are used for those components - if you want the correct lubricant - that is where to get the correct type maybe even find a second source for it if they provide a manufacturer and type. 
However some bearings are sealed bearings and if they are sealed they aren't to be lubricated - but replaced.