Melhorias para meu buscador no site

<form role="search" method="get" class="search-form2" action="<?php echo esc_url( home_url( '/' ) ); ?>">
                    <button class="btn-search" type="button">
                    <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24">
                        <path d="M15.5 14h-.79l-.28-.27C15.41 12.59 16 11.11 16 9.5 16 5.91 13.09 3 9.5 3S3 5.91 3 9.5 5.91 16 9.5 16c1.61 0 3.09-.59 4.23-1.57l.27.28v.79l5 4.99L20.49 19l-4.99-5zm-6 0C7.01 14 5 11.99 5 9.5S7.01 5 9.5 5 14 7.01 14 9.5 11.99 14 9.5 14z"></path>
                    </svg>
                    </button>
                        <input type="search" id="search-field2" placeholder="Escribe lo que necesites..." value="" name="s" autocomplete="on">
                        <button class="btn btn-lg btn-success" type="submit">Buscar</button>
                    </form>

$posts_array = get_posts(
    array(
        'posts_per_page' => -1,
        'post_type' => 'post',
        'tax_query' => array(
            array(
                'taxonomy' => 'tax', // nombre de la taxonomia
                'field' => 'term_id',
                'terms' => id, // Aqui los id de la taxonomia
            )
        )
    )
)