Cold messages to people in my field, do they work?, nurse's aide here

I sent 3 messages on a professional network and got two replies. I worked as a nurse's aide before this. I worry about bothering people. How do you phrase the request?

I wrote three short lines: who I am, why them and a small ask for fifteen minutes. About one in four said yes.

Follow up with a thank-you and a short update. One of my chats led to a referral a month later.