meta_query, how to search using both relation OR & AND?

I found the solution with some help. The code below worked perfectly.

    $args => array(
        'relation' => 'AND',
        array(
            'relation' => 'OR',
            array(
                'key' => 'title',
                'value' => $searchvalue,
                'compare' => 'LIKE'
            ),
            array(
                'key' => 'author',
                'value' => $searchvalue,
                'compare' => 'LIKE'
            ),
            array(
                'key' => 'genre',
                'value' => $searchvalue,
                'compare' => 'LIKE'
            )
        ),
        array(
            'key' => 'rating',
            'value' => $ratingvalue,
            'compare' => '=',
            'type' => 'NUMERIC'

        )
    )
);

After a bit trial and error I find a solution to this. This is logical I mean meta_query does not supports the array for field "key", but giving the array in "key", I'm getting the perfect solution. I may be sound crazy but it's working like charm.

$args => array(
    'relation' => 'AND',
    array(
        'key' => array('title','author','genre',),
        'value' => $searchvalue,
        'compare' => '='
    ),
    array(
        'key' => 'rating',
        'value' => $ratingvalue,
        'compare' => '=',
        'type' => 'NUMERIC'

    )
)

You only get a warning for "trim()" as we are passing an array instead of a string. Suppress that warning or Please add something if you find a better solution.