Clink on link menu link the detail of content disappear

My website use Flexi Containt, and now just have the problem around 2 day with my menu picture link to my full containt, When i click it show only menu name and part of menus, the full contain is disappear.
for more detail the problems please visit www.itandphotography.com/ and on the PHOTOGRAPHY BASIC you can click which one that you like to read more the real it will be open the full lesson but now the full lesson disappear.
Please give me an advice.
Thanks
Sokkheng

hello at first ... joomla and flexicontent version
did you change something in your site ?

Thanks for your reply, I'm always update my content and add more lesson only. Some time i clear catch in my joomla. Do you have any ideas? your guide line is very important for me.
Thanks

flexicontent and joomla version?
your adresse
www.itandphotography.com/index.p ... asics.html
is very very slow on firefox ...
and i see all content ....
can you post some screenshot ?

Thanks for your reply, please see creenshot attch with

The first www.itandphotography.com/ , youclick one of the Photography Basic and you will see only the menu not see the full contents.