Full text search in N1QL

i want to search for customer in my bucket i m currently using traditional RDBMS way to search for customer using N1QL LIKE query but i want to search and retrieve search data using FTS or any other method if available currently my code is for search is
$indexName = “def_search_customer_index”;
$firstQuery = SearchQuery::term(“spantik”)->field(“first_name”);
$secondQuery = SearchQuery::term(“spantik”)->field(“last_name”);
$thirdQuery = SearchQuery::term(“spantik”)->field(“phone”);
$query = new SearchQuery($indexName,SearchQuery::conjuncts($firstQuery, $secondQuery,$thirdQuery));
$result = $this->db_obj->query($query);
$this->printResult(“Conjunction Query”, $result);

The query is working fine but my question is how can i search on only type = '‘customer’ and retrieve customer fields like its name email or phone no. using this above aproach