$args = array(
            'posts_per_page'    => -1,
            'post_type'         => 'products',
            'post_status'       => 'publish',
            'tax_query'         => array(
                'relation'  => 'AND',
                array(
                    'taxonomy'  => 'subjects',
                    'field'     => 'name',
                    'terms'     => $shortcode_atts['subject'],
                ),
                array(
                    'taxonomy'  => 'plans',
                    'field'     => 'name',
                    'terms'     => $shortcode_atts['plan'],
                ),
            ),
        );
        $products = get_posts( $args );

        echo '<pre dir="ltr">';var_dump($args);echo '</pre>';
        echo '<pre dir="ltr">';var_dump($shortcode_atts);echo '</pre>';
        echo '<pre dir="ltr">';var_dump($products);echo '</pre>';

string(550) "Array
(
    [posts_per_page] => -1
    [post_type] => products
    [post_status] => publish
    [tax_query] => Array
        (
            [relation] => AND
            [0] => Array
                (
                    [taxonomy] => subjects
                    [field] => name
                    [terms] => אינטרנט
                )

            [1] => Array
                (
                    [taxonomy] => plans
                    [field] => name
                    [terms] => מסלול 10 גיגה
                )

        )

)
"
string(80) "Array
(
    [subject] => אינטרנט
    [plan] => מסלול 10 גיגה
)
"
string(3269) "Array
(
    [0] => WP_Post Object
        (
            [ID] => 284
            [post_author] => 1
            [post_date] => 2018-07-02 14:41:46
            [post_date_gmt] => 2018-07-02 11:41:46
            [post_content] =>
            [post_title] => מסלול 40 גיגה - וואלה מובייל
            [post_excerpt] =>
            [post_status] => publish
            [comment_status] => open
            [ping_status] => closed
            [post_password] =>
            [post_name] => someurl
            [to_ping] =>
            [pinged] =>
            [post_modified] => 2018-07-02 14:42:58
            [post_modified_gmt] => 2018-07-02 11:42:58
            [post_content_filtered] =>
            [post_parent] => 0
            [guid] => someurl
            [menu_order] => 0
            [post_type] => products
            [post_mime_type] =>
            [comment_count] => 0
            [filter] => raw
        )

    [1] => WP_Post Object
        (
            [ID] => 216
            [post_author] => 1
            [post_date] => 2018-07-01 11:03:02
            [post_date_gmt] => 2018-07-01 08:03:02
            [post_content] =>
            [post_title] => מסלול 10 גיגה - וואלה מובייל
            [post_excerpt] =>
            [post_status] => publish
            [comment_status] => open
            [ping_status] => closed
            [post_password] =>
            [post_name] => someurl
            [to_ping] =>
            [pinged] =>
            [post_modified] => 2018-07-02 09:22:24
            [post_modified_gmt] => 2018-07-02 06:22:24
            [post_content_filtered] =>
            [post_parent] => 0
            [guid] => someurl
            [menu_order] => 0
            [post_type] => products
            [post_mime_type] =>
            [comment_count] => 0
            [filter] => raw
        )

    [2] => WP_Post Object
        (
            [ID] => 60
            [post_author] => 1
            [post_date] => 2018-06-25 11:34:43
            [post_date_gmt] => 2018-06-25 08:34:43
            [post_content] =>
            [post_title] => מסלול 10 גיגה - פלאפון
            [post_excerpt] =>
            [post_status] => publish
            [comment_status] => open
            [ping_status] => closed
            [post_password] =>
            [post_name] => someurl
            [to_ping] =>
            [pinged] =>
            [post_modified] => 2018-07-02 09:22:33
            [post_modified_gmt] => 2018-07-02 06:22:33
            [post_content_filtered] =>
            [post_parent] => 0
            [guid] => someurl
            [menu_order] => 0
            [post_type] => products
            [post_mime_type] =>
            [comment_count] => 0
            [filter] => raw
        )

)
"