Hulbee Enterprise Search - Hulbee Enterprise Search is another powerful site search solution that intelligently retrieves information and documents regardless of their source or location.
SearchSpring - SearchSpring is an eCommerce site search tool.
SearchBlox - SearchBlox is an out-of-the-box Enterprise Search Solution built on top of Apache Lucene/Solr.
Varonis DatAnswers - Varonis DatAnswers is a leading enterprise search and discovery platform that deliver secure and relevant searches for authorized NAS, Windows files servers and share point users.
Wiser Search - Wiser Search for Lightspeed is a robust software created to provide reliable search functionality for e-commerce website owners.
ElasticSearch - Elasticsearch is an open source, distributed, RESTful search engine.