U.S. stocks closed lower on Thursday as a drop in energy stocks in a short trading session. The Dow Jones industrial average lost 50,44 points or 0.29 percent to end at 17,552.17 points. The S&P 500 Index dipped 3,30 points or 0.16 percent to 2,060.99. The Nasdaq Composite added 2.56 points or 0.05 percent to 5,048.49.