Uninstall many program

I am sorry for my inconvenience because I have many message on forum. During many days, I try self-study,I can understand a few about NSIS.
I do my installer but I still one problem which I can not find the answer.I hope somebody know can help me.
In my install, I will set up 4 program:
+ JDK
+ MySQL
+ My product 1
+ My product 2
However, when I create uninstall for my program,I do not know to call uninstall for MySQL, JDK,myproduct 1,my product 2.
Thank you for your help,

Either search the web using Google for available information for Java or installers in general (unattended has information about uninstallers as well), or execute their uninstaller string from HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall.