Filtering Columns when some adjacent columns are blank

I import a text file that displays outstanding parts orders. The order Number column only displays one number even if there are multiple parts ordered I.E. so if three parts are on order then the order number is displayed once with the other two underneath blank. I would like to filter the column that displays the amount of stock that is available so that even if the row has no stock but the other two have all three rows are displayed that reference the order number.
Regards Richard
Example Screen
Example.jpg

Thanks Dave your suggestion worked , I copied this insertion of =A(empty cell) and ctrl pasted into the rest of the empty cells , excel referenced to the cells above correctly , very clever.
I was hoping there was an easier method than actually having to select the empty cells , sometimes the spreadsheet is large. Is there is a way of copying that cell which has the =A ... reference to the cell above and pasting to a range that includes both types of cells with excel filling in the blanks?

Richard

Hi Dave,
I actually did not think of filtering first , I will use that instead of code , the "KISS" principal always works best
Thanks again