Ask many genuine scientists who have been doing research in a field for 30+ years and they can tell you how small the book knowledge is compared to the unexplored territory.
We're also taught by "genuine" scientist, people with PhDs, PhD/MD, and MDs on a daily basis about what we don't know.
I really appreciate this being taught, and from what little you wrote, I appreciate the humility shown. Please don't ever become a "big shot" that's too good to talk openly to people who are afraid about their health.
And you have a warped view of what Doctors are. They are not Research Scientists. They are not there to try out cutting edge techniques and medicines. They are not there to be the world's foremost knowledge on everything medical.
They are there to give you conservative, boring advice vetted by the authorities for specific ailments. Anything more serious they recommend you to see specialists.