How does a google search speak to my niche?

Still crafting my niche. Conceptually I completely understand the need for specificity with a niche, and I see how that translates to marketing the solution. I also understand the need to ask “what is the problem my target market is googling?” But linking the two together is stumping me. Realistically most people won’t google search “weight loss for female physicians over 50 years old with 100 pounds to lose”; they seem more likely to just google “weight loss”. Thoughts? Have I just been using Google incorrectly all these years? 😉