need help, could someone tell me how to remove the frond bumper for 2008 camry?

[donga2000]

I have little damage on the front bumper of my 2008 camry. The damaged part need to be push out to the original position from inside of bumper. But after removed all the screws and clips I can see, the front bumper still won't come out, espetially on the left and right end of bumper. I am afraid that the bumper will be damaged if I use too much force on it. Could someone tell me what I should do? Thanks a lot.