Hi Chheang!
This is not quite what you need.
1) Enable profiler in the Webmaster kit module.
2) Go to the slow page and you will see report at the bottom of this page. It will look like this:
http://awesomescreenshot.com/0433fkgec1
3) Check reference points and if there is any red records (you note them), please let me know about them. Alternatively, you can make the snapshot of entire page (services like awesomescreenshot allows to do that) and send it to me.
Tony.