Have SearchWP perform searches in WooThemes' Sensei

functions.php

<?php

// SearchWP/Sensei compat
function searchwp_sensei_compat() {
	if ( is_post_type_archive() && is_search() ) {
		add_filter( 'searchwp_outside_main_query', '__return_true' );
	}
}

add_action( 'parse_query', 'searchwp_sensei_compat' );