In January, Jon Bach got laid off as a director at eBay, where he had worked for 13 years. He loved his job, so he was disappointed. But he didn't panic. The unemployment rate was near a five-decade low, and he had 30 years of experience in the tech industry. How hard could it be to find another job?Pretty hard, it turned out. After applying for 135 openings, Bach has received 91 nonresponses, 42 rejections, two callbacks — and zero offers. "I don't know what's going on," he says. "I've been doi...