Redirect with htaccess all searches containing ".pl"

My database crashes several times per day. In my error log I’ve got a lot of query searches of SOMETHING.pl, so, I want to redirect with .htacess file all urls containing “.pl” to my index page, and I’m having problems with that since there is no a “for dummies” guide for .htaccess. Remember I have a dot (.) in “.pl”.
Can you tell me how to redirect all urls having “.pl” to my index page?
This is what I have in my error log:

[17-May-2016 19:40:49 UTC] Error Lost connection to MySQL server during query de la base de datos de WordPress para la consulta SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND (((wp_posts.post_title LIKE ‘%przyjacielski.pl%’) OR (wp_posts.post_excerpt LIKE ‘%przyjacielski.pl%’) OR (wp_posts.post_content LIKE ‘%przyjacielski.pl%’))) AND (wp_posts.post_password = ”) AND wp_posts.post_type IN (‘post’, ‘page’, ‘attachment’) AND (wp_posts.post_status = ‘publish’) ORDER BY wp_posts.post_title LIKE ‘%przyjacielski.pl%’ DESC, wp_posts.post_date DESC LIMIT 0, 10 realizada por require(‘wp-blog-header.php’), wp, WP->main, WP->query_posts, WP_Query->query, WP_Query->get_posts, W3_Db->query, W3_DbCache->query, W3_DbCallUnderlying->query, W3_Db->query, W3_DbProcessor->query, W3_Db->default_query

Thanks.