Reload collection

To clear a collection you can call:

$this->_myCollection->clear();

To reload a collection you can call:

$this->_myCollection->load();

If you applied filters, you can reset collection with :

$this->_myCollection->clear()->getSelect()->reset(\Zend_Db_Select::WHERE);

Then :

$this->_myCollection->addFieldToFilter('field', $singleItems->getSomething());
$this->_myCollection->load();