And sometimes that's how it gets started (from travel pick ups). I took the liberty to identify your notes on the Banknote Museum site (or BNM for short).
P-55 South Korea 5000 Won:
http://www.banknote.ws/COLLECTION/c.../KOS0055.htm
P-57 South Korea 50,000 Won:
http://www.banknote.ws/COLLECTION/c.../KOS0057.htm
P-120 Vietnam 20,000 Dong:
http://www.banknote.ws/COLLECTION/c.../VIE0120.htm
Note: BNM has stated that the first two numbers of the serial # indicate the year the 20,000 Dong was issued. That means your note comes from 2020.
P-123 Vietnam 200,000 Dong:
http://www.banknote.ws/COLLECTION/c.../VIE0123.htm

























