You can't
A desktop HD has a typical reliable lifespan of 4 years or so, hence their commonly being guaranteed for that sort of length of time.
If you wanna use them for longer than that, just make sure you have your data backed up. You may get lucky and they may go on without issue for many years, or you may get unlucky and have one die on you with little or no warning. Once the errors start showing up however, though you fix them, more are likely to start appearing, and this is typically a sign that the drive is starting towards the end of its life and you should consider replacing it
An alternative thought - a good use for old drives is in a Drobo