Faceted search 

"Faceted search, also called faceted navigation or faceted browsing, is a technique for accessing information organized according to a faceted classification system, allowing users to explore a collection of information by applying multiple filters. A faceted classification system classifies each information element along multiple explicit dimensions, called facets, enabling the classifications to be accessed and ordered in multiple ways rather than in a single, pre-determined, taxonomic order." Source: https://en.wikipedia.org/wiki/Faceted_search

This requires Elasticsearch and is configured at tiki-admin.php?page=search -> Search Results

As of July 2016: If you want to use Faceted Search, you should stick to Elasticsearch 1.x Facets have been removed in 2.0, and replaced by the "more powerful and flexible aggregations framework. " but the Tiki code has not yet been updated to use this. Source: https://www.elastic.co/guide/en/elasticsearch/reference/2.0/breaking_20_removed_features.html#_facets_have_been_removed fixed in 15.3

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