3.7

SELECT
    *
FROM
    (
    SELECT
        `ОТ`.`No`,
        COUNT(`Код`) AS kol1
    FROM
        (
        SELECT
            `СЛ`.`Код`,
            `СЛ`.`No`,
            COUNT(`ИЖД`.`Код`) AS kol
        FROM
            `СЛ`
        JOIN
            `ИЖД`
        WHERE
            `СЛ`.`Код` = `ИЖД`.`Код`
        GROUP BY
            `СЛ`.`Код`
    ) T1
JOIN
    `ОТ`
ON
    T1.`No` = `ОТ`.`No`
WHERE
    T1.kol = 2
GROUP BY
    `ОТ`.`No`
) T2
WHERE
    kol1 > 3