Is there somewhere I can learn about how the primary address street field is handled? When exporting I'm having issues with multi-line addresses in a .csv file.

Essentially, when exporting a Contacts report to use as a physical mailing list, all of the addresses that were more than one line in the "primary address street" field caused errors when uploading to the USPS system we were using for a bulk mailing. I need to force that to export as one line, or multiple fields - is that possible? Or is there documentation I can read about how it is handled to try and adjust it in excel after exporting.