WP Sql query multiple where clause

You can try this with WP_User_Query instead:

$args = array (
    'meta_query'    => array(
        array(
            'key'   => 'newsletter',
            'value' => 'true',
        ),
        array(
            'key'   => 'account',
            'value' => 'false',
        ),
    ),
    'date_query'    => array(
        array(  
            'after'     => '2015-01-13 00:00:00',
            'inclusive' => true,
        ),          
     ),
);

$user_query = new WP_User_Query( $args );

where I assume your user meta values are boolean strings, i.e. 'true' and 'false'.