Elastic search is a free, super-fast search tool with a powerful, RESTful API. Depending on how you use the API, it can deliver significantly better search results than a typical Boolean search in vtiger.
We did a custom project for a Vtiger client to deliver better results faster. The client had hundreds of thousands of contacts and Elastic Search for Vtiger sped their search up to less than 1 second. In addition, searching comments and/or the description field brought back more relevant results.
Contact us if you would like to learn more.