How to add images for a product like virtuemart demo

[The Godfather]

Hi

I'm using Virtuemart for the first time.
I Bought Megadeal Shaper template which had installed Virtuemart on itself.

I want to add a product like LED TV's, so I Have to add some images to show all dimension of that TV.
But when i add more than one images, This Happens: http://tcltehran.com/index.php/shop/computers-gaming/apple-macbook-pro-detail

But i want my created products to be like this: http://demo.virtuemart.net/index.php/2012-01-13-09-33-20/virtuemart-default-layout/mobile-phones/apple-iphone-4-detail

I mean additional images should be placed under the main image in thumbnail size ( just like demo )
But in the product i created, It isn't . The second image is placed under the first one.
Do i need to install any plugin ? can you please recommend some ? In which websites i can download or buy them?

Thanks for your help

[Maxim Pishnyak]

Plugin for Firefox - http://forum.virtuemart.net/index.php?topic=102850.0

[The Godfather]

Thank you so much Mr. Pishnyak
I Have Firebug already and i know how to use it , But the question is How can i do what i wanted ?
Isn't there any plugin to do this ?

[Maxim Pishnyak]

I mean additional images should be placed under the main image in thumbnail size

Digg in Firebug: why size is so big? Etc.

[The Godfather]

I Tried using firebug, but i couldn't do what i wanted.

Can you please do me a favor and help me more and say what to do ?

so much thanks