entry and exit policies

Hi. I have visit visa (F). Im here in guangzhou and staying here for two months. May 6- july 5. With one entry level. I would like to visit hongkong on a weekends stay there for 2 nights and comeback here in china. But i only have one entry. Im a filipino and dont need one going to hongkong. How can i change or apply for multiple or double entry level? Please help. Thank you.