CREATE TABLE table_30303 ("Year Location" TEXT, "Mens Singles" TEXT, "Womens Singles" TEXT, "Mens Doubles" TEXT, "Womens Doubles" TEXT)

Who won the mens doubles when wang hao won the mens singles?
SELECT "Mens Doubles" FROM table_30303 WHERE "Mens Singles" = 'Wang Hao'
SELECT "Mens Doubles" FROM "table_30303" WHERE "Mens Singles" = 'Wang Hao'