Find a job first, get offer letter and request your boss to provide you with NOC. Once you join the new company, the NOC must already prepared by your old company. Your new company will tell you other requirements they need for the transfer like Computer ID of your previous co. etc. You need to have NBI Clearance from Philippines, ribboned and authenticated by DFA in the Philippines and Stamped by Philippine Embassy here in Qatar and attested by Foreign Affairs of Qatar.