File e-tickets with PNR, airport code and date of travel

I need help with saving e-tickets for my flights, which I receive in a PDF format with the following scheme:
date_to-date_return-dep-des-PNR.pdf where
date_to: departure date (in YYYY-MM-DD)
date_return: return date (in YYYY-MM-DD)
dep: 3 letter airport code of departure airport
des: 3 letter airport code of arrival airport
PNR: Alphanumeric code of length = 6
I have managed to set this up for a journey that only has one destination say - BOS-JFK, but I can't figure out how to get it to handle tickets with multiple stops say BOS-CLT-LGA-ORD
As you can see, I've managed to name the file, but it isn't accurate.
The top portion of what I get from the airline can be found here on DropBox: https://www.dropbox.com/s/uoz3mf5mrbyo6o3/2017-08-24-2017-08-24-BDQ-BOM-BOM-HMJVWQ.pdf?dl=0
date_to-date_return-dep-des-PNR.pdf where
date_to: departure date (in YYYY-MM-DD)
date_return: return date (in YYYY-MM-DD)
dep: 3 letter airport code of departure airport
des: 3 letter airport code of arrival airport
PNR: Alphanumeric code of length = 6
I have managed to set this up for a journey that only has one destination say - BOS-JFK, but I can't figure out how to get it to handle tickets with multiple stops say BOS-CLT-LGA-ORD
As you can see, I've managed to name the file, but it isn't accurate.
The top portion of what I get from the airline can be found here on DropBox: https://www.dropbox.com/s/uoz3mf5mrbyo6o3/2017-08-24-2017-08-24-BDQ-BOM-BOM-HMJVWQ.pdf?dl=0