Help with lens for Sony DSLR a390

[Texas Mom]

I recently purchased my first DSLR camera and I need some advise about the lens. The camera came with the standard 18-55mm lens but it doesn't zoom in as I expected. I've had this camera less than a week so I'm still trying to get familiar with the settings etc. I don't know if this zoom issue is because I'm not using the settings correctly or if I'm expecting too much or if that is all there is and I need to invest in a better zoom lens (I would have no idea which one buy). Can anyone give me some advise about this? Thanks - Shannon