I have to add couple of cost fields on product display in virtuemart, and appearance box near each cost area

For instance, whenever you buy the product, cost is dependent on weight, and you have to choose under control box

50ml 75ml 100ml

and near each checkbox, product cost input area is going to be displayed.

How you can understand this factor and it is there any solution, that already done

Thanks, Ahmed.

You have to setup child (sub) items of the primary product. By doing this you could have the description and pictures within the parent product and every child product may have a characteristic and cost connected by using it. Possess a google on "virtuemart setup child items" or something like that like this.