Every time a site is crawled, a new index is created. You can customize the settings that are used for this index in two ways.
The first way would be by adding a meilisearch.indexSettings JSON value to the extra attribute in the site_search_configs. In meilisearch.indexSettings you can put any of the list settings that Meilisearch provides.
Here's how that value you would put in extra if you only want results based on the url and description fields in the index.