Provide support to execute mail merge with commands contains AND and OR operators Validated

                    //Creates an instance of the MailMergeDataSet.

                    MailMergeDataSet dataSet = new MailMergeDataSet();

                    //Creates the mail merge data table in order to perform mail merge.

                    MailMergeDataTable dataTable = new MailMergeDataTable("Customers", GetCustomers());

                    dataSet.Add(dataTable);

                    dataTable = new MailMergeDataTable("Orders", GetOrders());

                    dataSet.Add(dataTable);

                    List<DictionaryEntry> commands = new List<DictionaryEntry>();

                    //DictionaryEntry contain "Source table" (key) and "Command" (value).

                    DictionaryEntry entry = new DictionaryEntry("Customers", string.Empty);

                    commands.Add(entry);

                    //Retrieves the customer details.

                    entry = new DictionaryEntry("Orders", "CustomerID = %Customers.CustomerID% AND OrderName = %Customers.CompanyName%");

                    commands.Add(entry);

                    //Performs the mail merge operation with the dynamic collection.

                    document.MailMerge.ExecuteNestedGroup(dataSet, commands);