C# .NET - how to add new controls for the existing controls in visual studio 2005

i have some controls in my project. but i require c1 components like tdbgrid, dropdown...etc. but i'm not able to add new controls to the new tab. i followed the procedure given in many articles like right clicking the tabs Add new tab will visible there i added new tab and right clicking there i selected choose items and selected the named controls but after clicking ok i have not seen those controls in that tab.... i really want solution because i require this control in my project can any one give solution for this problem.....................