string(252) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=b2b%E6%A8%A1%E5%BC%8F%E4%B8%BE%E4%BE%8B%E8%AF%B4%E6%98%8E%E6%80%8E%E4%B9%88%E5%86%99 => Failed to connect to 101.89.117.144 port 38017: Connection refused"
b2b模式举例说明怎么写
