Try..
gvSearch.DataSource = dSetTEMP.ITEM_SEARCH_COLTWO;
gvSearch.DataBind();
And Set..
ShowHeaderWhenEmpty and EmptyDataText propery in gridview. like this
<asp:gridview id="gvSearch" runat="server" allowpaging="false" autogeneratecolumns="False" emptydatatext="No Records Found" showheaderwhenempty="True" width="100%" xmlns:asp="#unknown">
</asp:gridview>