How to convince one’s parents for the Truth? And how to convince doctors?

The following excerpt is from a samvaad (dialogue) session with Acharya Prashant.

Question (Q): Acharya Ji, there is someone in my life, who is close to me. But, when I talk to that person, the person doesn’t listen to me. But, I know that deep down, he is a sensitive person, and wants the Truth. How do I deal with this person?