Help for Aimeos

Hello ! i have a problem with cache into components ; it's nice to cache some components but i have a component which normally is happen to change when i do some action but it don't ( in my case it is component body with catalog items) ; how can i clear cache in some conditions in the controller of myextension ;
look that i used this->addMetaItems(item ...) but it seem like i don't understand how it work !
Need explanations please !

The component that cache content has a modifyBody() method which is used to replace dynamic content from the cache fragments. What exactly do you need to update and when?