Minimizing form

I have write a program in delphi wich hase some forms. As the other programs in delphi when I minimize the main form of programm it miimized like other windows program, but when I minimize other forms, i doesn't go down to the task bar, and covert to a small rectangle and go to the left bottom corner of the screen.
Ho can make it like other windows programs, that always go to the task bar when the user minimize any forms?