Question: Who were the womens doubles when the mixed doubles were zhang nan zhao yunlei on the tour all england super series?
Schema: create table table_27753492_2 (womens_doubles varchar, mixed_doubles varchar, tour varchar, PRIMARY KEY (womens_doubles))
SQL: select womens_doubles from table_27753492_2 where mixed_doubles = "zhang nan zhao yunlei" and tour = "all england super series"