Nicolaslopezj\Searchable\SearchableTrait::makeJoins PHP Method

    protected function makeJoins(Builder $query)
    {
        foreach ($this->getJoins() as $table => $keys) {
            $query->leftJoin($table, function ($join) use($keys) {
                $join->on($keys[0], '=', $keys[1]);
                if (array_key_exists(2, $keys) && array_key_exists(3, $keys)) {
                    $join->where($keys[2], '=', $keys[3]);
                }
            });
        }
    }