It appears that you have made the change to line 172:
objWorksheet.Cells(2, colDescription).Value = c.RootComponent.GetStringAttribute("DENOMINAZIONE")
Now make the same change to line 415:
xlsWorkSheet.Cells(intWriteRow, colDescription).Value = child.GetStringAttribute("DB_PART_NAME")
"I've done the modification you have suggested, but doesn't function."
"Doesn't function" is pretty vague. Do you get an error message? incorrect values? computer crashes?
If you are running the journal on native NX (not Teamcenter), then you will have to change lines 175 and 417 to return the desired attribute instead of the part file name.
Are you using native NX or some sort of PLM system (such as Teamcenter)? This may affect where you need to get the "description" attribute from.