South Korean President Park Geun-hye left for Russia on Wednesday for a summit of the world\'s top 20 economies and a series of bilateral meetings with other leaders in what would be her debut in multilateral diplomacy. Russia\'s second-largest city of Saint Petersburg is the first leg of Park\'s two-nation trip that will take her to Vietnam for a state visit billed by officials as the kickoff of her \"sales diplomacy\" drive aimed at helping boost South Korea\'s slumping economy.