incremental parameter inside Xpath + nested tables/lists/ or subreports

I use an xml as a dataset (xpath) and went to display all suboffers that exist in a cart. this is my xml tree

<carts>

       <cart>

               <subOffer  id="MainOffer.SubOffer1.Id"  value="test1"" />

                <subOffer  id="MainOffer.CartLine.Price"  value="1255"" />

                <subOffer  id="MainOffer.SubOffer1.Name"  value="test1"" />

                <subOffer  id="MainOffer.SubOffer2.Id"  value="test1"" />

                <subOffer  id="MainOffer.SubOffer2.Name"  value="test1"" />

                <subOffer  id="MainOffer.SubOffer3.Name"  value="test1"" />

                <subOffer  id="MainOffer.SubOffer3.Name"  value="test1"" />

        </cart>

        <cart>...........</cart>

       <cart>...........</cart>

</carts>

so i want to get all suboffers name value (//carts/cart/subOffer[@id='MainOffer.SubOfferX.Name']/@value).

i tried to use nested tables/lists/subreports but no success

Can someone plz tell me how to get all suboffers name value by each cart.

Thank you in advance