Most Helpful Girl
Find a girl who is interested in that stuff. They do exist. Don't settle for the superficial ones who only worry about whether or not the rain will ruin their $500 handbag.
I'm actually quite interested in the topics that you mentioned. You just gotta find a girl who shares your interests.
Most Helpful Guy
Don't talk about yourself - talk about her. Ask her open-ended questions, and listen to what she says - don't just nod your head. . . listen.
You'll find something in what she says that will correlate to something you like and you'll find something to talk about, but make sure the conversation goes back to her. Build rapport with her, show interest in the things she likes, and all will go well.
If you like business and 'market trends', then view this as a sales pitch. In order to sell something, you'll first want to build rapport by showing interest in the person you're selling to. And, obviously, you're the product you're selling.