Advanced search_criteria usage

Hey there,
So I’m doing an AJAX that populates data from a selected past entry. All that works dandy. I was just hoping to kick it to the next level. My code is working fine, I’m just hoping for some direction on the best way to make use of the $search_criteria array.

$entries1 = GFAPI::get_entries(
		$search_criteria = array(),
		$sorting = array(
			'key' => 'date_created',
			'direction' => 'DESC'
		$paging = array(
			'offset' => 0,
			'page_size' => 100
		$total_count = null

Right now the documentation is lacking, but let;s say I want to look up an entry by a certain field in the entry. Would that be:

$search_criteria = array(
     '2' => 'Boom',


So here is an example. I can’t seem to get:

$search_criteria = array(
	'created_by' => 1,

To work properly. But I can get:

$search_criteria = array(
	'status' => 'active',

To work fine. Its a bit annoying.

What am I missing?