Everyone has secrets or things they want to keep to themselves. It could be something as simple as a new purchase or something more serious like a divorce. If you want someone to open up to you, there are a few steps you can take.
So, before you do anything else, try the following:
Start the conversation without asking your interlocutor to speak to you.
Ask something general, without getting off topic. Let the other person talk about themselves, without interrupting them, and make them feel comfortable. For example, if you're on a date and want to know why your partner's previous relationship ended, you shouldn't immediately ask them about it. You'll want to ask some more general questions. After all, no one talks openly with someone else if they don't feel comfortable, right? Let the other person relax, without interrupting them by telling them similar stories of your own, and that's how you'll be able to 'unlock' them.
Show compassion and responsibility.
Always show understanding and compassion. When talking to someone face to face, look them in the eye. If you are talking on the phone, make it clear that you are paying attention and listening to the other person. Talking about personal and sensitive issues is difficult. Talking to someone who is not listening or paying attention is even more difficult. Understanding and paying attention to the other person sends the signal that you are there and are willing to help or reassure your interlocutor. If you want to learn something secret, keep your cool and be present in the conversation as a very good listener.