How do I ask for an informational chat? - what worked for you?

I sent 15 messages on a professional network and got two replies. There are 15 people counting on me, so I am trying to be careful. I worry about bothering people. Did any turn into leads?

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

I asked what they wish they had known at my stage. People enjoy answering that.