[eluser]boltsabre[/eluser]
okay, what do you get if you do it in the above way, if you're not getting any error messages try var_dump to see what you get, otherwise, can you tell us what the error message is?
Code:
//in your controller
$search_result = $this->my_model_name->posts_that_match_search_term($search_term);
var_dump($search_result);
//actually, you could just var_dump($return) from inside your model, it's up to you!