I found solution by using ajax to request to load another form.

self.do_action({
             views: [[false, 'form']],
             view_type: 'form',
             view_mode: 'form',
             res_model: 'product.product',
             type: 'ir.actions.act_window',
             target: 'current',
              res_id: product_id,
 });

Voathnak,

Can u post the full code for opening openerp url using ajax? i'm totally "lost" in php, mainly i write my code using java..

Thanks..

Ignatius