Send "changed keywords" information via script

[Josu Gomez Perez]

Hi! I'm struggling these days trying to get a script that
-Sends a daily email
-With the information of the changes happened in an account the day before ("YESTERDAY")
-By an specific user
(so far I got it)

-that includes the information of the keywords changed (paused or enabled).
This step I haven't been able to get it. It seems change_event tells you if changes have happened inside an ad_group (with ad_group_criterion), but not the specific keywords affected.

old_resource and new_resource JSON files don't contain that information, as far as I have been able to look.

Any idea what could I try next? Thanks!