$model = new <your model class>;
$criteria = new CDbCriteria;
$criteria->condition="type=:type AND category=:category AND (color=:color1 OR color=:color2 OR color=:color3)";
$criteria->params=array(':type'=>1, ':category'=>1, ':color1'=>'black', ':color2'=>'blue', ':color3'=>'red');
$results = $model->findAll($criteria);
$criteria = new CDbCriteria();
$criteria->condition = "type = 1 AND category = 1 AND (color = 'black' OR color = 'blue' OR color = 'red')"; // you may supply parameters here