How to see the running background task using pid in ssh – Apache

I want to see the background process which i run from the browser.

i have process id. but when i try to see ps -p pid, it does not show me the background process which are running on the server. This script actually run for 30 min and do several task. But some time it hang, I want to see the process which is internally executed when i run.

Please help me out.

Thanks in advance.