Looks like Don Ho added the RegEx OR | operator to the Notepad++ native Find in the
latest version of Notepad (ver. 6.1.1).
Download Notepad 6.1.1 from here
Install Notepad 6.1.1, then go to
Search->Find
Find what: action(421|732|983)
Search Mode: (*) Regular Expression
Click on the Find Next button