.....there's a way of increasing the chances of finding magic, is there?

I had to restart my game because I did something stupid in my last one -I don't want to explain cause I'm too embarrassed by it. Last time I found magic the first time I explored a crack. Now I can't seem to find any no matter what. I keep sending my chief down since he's got a max for gathering thinking that will help, but all the doofus finds is tech points.