Sitecore uses Solr as a search engine to index and retrieve content from the Sitecore database. Solr is designed to provide fast search results, even with large amounts of data. It also provides advanced search features, such as faceted search, fuzzy search, boost, and stemming.
SearchStax Cloud lets developers set up and deploy Solr infrastructure for Sitecore in minutes and removes the pain of managing and supporting Solr deployments. Hundreds of Sitecore customers are currently using SearchStax Cloud to efficiently and effectively manage their Solr infrastructure.
See the Sitecore/Solr Compatibility page for more information on recommendations for the combinations of Sitecore and Solr.
Do not hesitate to contact the SearchStax Support Desk.