I've recently, noticed, my cockatiel, to have something in her eye, my dad looked at it under a magnifying glass and looks like a bit wax, but we're not entirely, sure, how could we go about removing this, safely ?
You should not try to physically do anything to remove what is in there. You can encourage the bird to bathe, so that if there is a seed hull stuck in there it will come out.
If it does not come out, you need to make an appointment with an avian vet. It could be a growth, or even if it is something stuck in there, it will become infected if not removed.