Warren Buffett says it's important to know which deals not to take (BRK.B:NYSE)

"The world is full of people offering things for you to do. The key is to find the ones worth doing," Berkshire Hathaway (BRK.B) (BRK.A) Chairman Warren Buffett said Saturday. "I think it's all working," Buffett said, referring to the company's operations Newsletters for Every Investor Get daily,…