Retrieve null data from SQL server into datatable

Question

My program able to read excel into datatable using epplus C# and there's a barcode (3) column with data. I add & get invtID data column from SQL Server based on data in barcode (3) column. 

The problem is, I managed to get the data but not in order as it should be followed by the data in barcode (3) column. Even when there is no invtID match with barcode, it doesnt print an empty cell or null. I really need help how sql server to read the null or empty data and print it as empty cell.

The order I want to get. The no need means that 1 barcode have 2 bookcode, it is possible to just get either one

 

The order i received