How can you open search dialog in javascript with a filter


as per title - how can we set the filter for search dialog in javascript

var param = {
                title: title,
                aras: top.aras,
                type: 'SearchDialog',
                dialogWidth: 700,
                dialogHeight: 450,
                itemtypeName: 'Part'            
            };'iframe', param).show("iframe", param);
Is it possible to catch an even of this dialog?
Or how can we manually run the opened dialog "search"? The dialog is an iframe and the dijits have no ids 
I managed to make it work for test case with, mind you i cannot use this in reality, scope issues
Thank you