public function getColumn($columnKey)
    {
        $columns = $this->searchable();

        if (array_key_exists($columnKey, $columns)) {
            return $columns[$columnKey];
        }

        foreach ($columns as $column) {
            if ($column === $columnKey || ends_with($column, ".{$columnKey}")) {
                return $column;
            }
        }
    }