Cold messages to people in my field, do they work?

I want to talk to people in a new field but I hate cold messages. This is my first time dealing with any of this. I want advice, not a job directly. How do you phrase the request?

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

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