Someone can give useful tips on how to improve one’s work.
Someone means "an unknown person" - in the sense that it's definitely one person, but you don't know who that is for whatever reason.
Without context, it seems like you are contradicting yourself here because you don't know who this person is, yet you are claiming he can give useful tips on how to improve one's work - you couldn't really say that for sure unless you knew who the person was.
This is different than saying anyone:
Anyone can give useful tips on how to improve one's work
Anyone means "of any possible persons" - we're not talking about a specific person anymore - and seems more like what you were trying to say.