Here is the pull request resolving this issue: https://github.com/discourse/discourse/pull/4981 - added infinite loading of search results, in total 10 pages of 50 results are loaded when scrolling which results in 500 search results (not more because of the performance, even Google limits maximum 1000 results per query). If there are still more results, it tells users to narrow down their search criteria. Any comments and suggestions are welcome.