public static boolean search(String a, String b, String c) {
    int len = c.length();

    for (int i = 0; i <= a.length() - len; i++)
        if (a.substring(i, i + len).equals(c))
            for (int j = 0; j <= b.length() - len; j++)
                if (b.substring(j, j + len).equals(c))
                    return true;
    return false;
}