WordPress Search Filter

<?php
function adopt_custom_taxonomy_dropdown( $taxonomy, $orderby = 'date', $order = 'DESC', $limit = '-1', $name, $show_option_all = null, $show_option_none = null ) {
    $args = array(
        'orderby' => $orderby,
        'order' => $order,
        'number' => $limit,

    );
    $terms = get_terms( $taxonomy, $args );
    $name = ( $name ) ? $name : $taxonomy;
    if ( $terms ) {
        printf( '<select name="%s" class="postform">', esc_attr( $name ) );
        if ( $show_option_all ) {
            printf( '<option value="0">%s</option>', esc_html( $show_option_all ) );
        }
        if ( $show_option_none ) {
            printf( '<option value="-1">%s</option>', esc_html( $show_option_none ) );
        }
        foreach ( $terms as $term ) {
            printf( '<option value="%s">%s</option>', esc_attr( $term->slug ), esc_html( $term->name ) );
        }
        print( '</select>' );
    }
    }

//The following is then used to pull the results onto a results template:
?>
<?php
        if (isset($_GET["farm-type"]) && empty($_GET["location-farms"])){

        $farm_type = $_GET["farm-type"];

        $myquery1['tax_query'] = array(
            array(
                'taxonomy' => 'farm-type',
                'terms' => array($farm_type),
                'field' => 'slug',

            ),
        );
        query_posts($myquery1);

        }
        ?>

        <?php
        if (isset($_GET["farm-type"]) && isset($_GET["location-farms"])){

        $farm_type = $_GET["farm-type"];
        $farm_location = $_GET["location-farms"];

        $myquery2['tax_query'] = array(
            array(
                'taxonomy' => 'farm-type',
                'terms' => array($farm_type),
                'field' => 'slug',
            ),
            array(
                'taxonomy' => 'location-farms',
                'terms' => array($farm_location),
                'field' => 'slug',
            ),
        );
        query_posts($myquery2);

        }
        ?>