You might notice the search is faster and the website. @CIAS and @tirial have replaced Wordpress search with a professional search engine after a user kindly donated a licence. Integrating it with Wordpress is taking some time, so the search results might be a bit off for couple of days. If you notice anything, or want to suggest tweaks, please let us know. This should deal with the issue with multiple pages of results overlapping, and the slow speed as the site grows.