The Fed may have to do more to restore the flow of credit , Fed Vice-Chairman Donald Kohn said on Friday. U.S. policymakers and central banker must remain "very flexible and open to policy actions that had no precedent," Kohn said, pledging that policy-makers would "continue to adapt our policies as necessary to accomplish," a recovery of the financial system and consequently the broader economy. Nevertheless, many financial market sectors remain under "considerable stress"...