sql report server horizontal tables

with tow table and write below function and call functions in tables expresions
call this function in expresion for table that to show items and try to invisible it by color it white

Public Dim lst As String = ""
Function getGoodsLst(ByVal text As String) As String

        lst += text + " - "
        Return lst

    End Function

call this function in expresion for table to show item like data1,data2,...

Function getGoodsLst1() As String
        Return lst
    End Function