wordpress_search_visitor_ip_block.php

// Get user IP in WordPress
function get_the_user_ip() {
	if ( ! empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
	//check ip from share internet
	$ip = $_SERVER['HTTP_CLIENT_IP'];
	} elseif ( ! empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
	//to check ip is pass from proxy
	$ip = $_SERVER['HTTP_X_FORWARDED_FOR'];
	} else {
	$ip = $_SERVER['REMOTE_ADDR'];
	}
	return apply_filters( 'wpb_get_ip', $ip );
}

function search_visitor_ip_block($query) {

	// Visitor search limit
	$visitorIPLimit = 20;

	$visitorIPCount = get_option( 'visitor_ip_count'.get_the_user_ip() );
	$visitorIPCount += 1 ;

	update_option( 'visitor_ip_count'.get_the_user_ip(), $visitorIPCount );

	if ( $query->is_search ) {
		if( $visitorIPCount >= $visitorIPLimit){
			wp_die('Sakin ol şampiyon?');	
		}
    	}
	return $query;
}

//hook filters to search
add_filter('pre_get_posts','search_visitor_ip_block');