Being a Datu, formerly I had holding a territory n part of PI, could I claim it back under my control ?

I suppose you are referring to Bohol, sorry to say they do not honor those titles there anymore. I think you can be one during town fiestas, and you can claim your few minutes of fame during the 'coronation' and that's it. I think all the lands there are titled so too late if you have a claim. :)