Finding my audience

I’m a physician that has worked in the pharmaceutical industry for 15 years. I am now an executive level in pharma/biotech industry. There are many physicians that want to consider/explore/enter pharma/biotech as a career but they do not know how. MDs are not trained at all in business, in pharma/biotech (in fact they are often taught it is “dark side”). I have a coaching/consulting business to help these MDs. I’ve built my email list over 3 months to 150 people. I am struggling to know how to reach my target audience. I’m on Facebook and focused to physician side gig groups, etc. but that is not wide enough to capture enough clients. I’m seeking information on how to find/target my audience.