magento2 – get specific columns from left join

I’m trying to join two tables like below

    $objectManager =  MagentoFrameworkAppObjectManager::getInstance();

    $collection = $objectManager->get('AdvanceModuleModelMethod')
    ->getCollection()->addFieldToFilter('stores', ('finset' => $store_id));

    $collection->getSelect()->joinLeft( ('shippingrate'=> 'shippingrate'), 
    'shippingrate.method_id = main_table.method_id', ('main_table.method_id'));

This is return all data from two tables. I couldn’t get specific columns from the end result.