ziprecruiter inc an online job search and recruiting company sold 550 million of junk bonds friday in its firstever trip to the us highyield market as employers confront spot shortages of workers and high turnover the company probably will use at least some proceeds from the offering to finance acquisitions according to moody’s investors service which is rating the notes b2 or five steps below investment grade ziprecruiter said the money it raises may be used for capital expenditures investments and working capital