How to Repair Broken Screw?

I Have a HP Pavilion DV2 1003 AX Notebook, But Last Week, I Try to Open the case so when i want to open the keyboard screw at the back it was stuck (can't be opened) so i check that screw and i see the screw was broken.. i have try so many screwdriver but still the same :( anybody know hot to open that screw ?

just got an offer of a screw extractor, branded "ELORA" but still not sure.. anybody know how to get the ifixit precision screw extractor set at indonesia ? or the nearest country from indonesia ?