What other sector should I invest besides Tech / AI?

AI / Tech is pretty much my specialty because of my job but, I want to diversify. I've held VOO, Brk.b but that's about it. Whenever I go into other sectors I feel i'm just randomly guessing. And usually bad things happen for me. I've considered costco, novo nordisk, eli lily, byd (tesla competitor). Novo nordisk was an interesting one because my doc recommended i try ozempic for diabetes and i start losing weight and I thought a lot of americans would get this prescribed. What i didn't expect was that Medicare was going to enforce a maximum payout for the prescription and tank the stock. Kind of dodged a bullet there. Is any industry growing besides AI / tech?