Notepad++ Search For 3 Character -

i have huge textfile different names. how search names include 3 characters or 3 characters long?

press ctrl+f , enable regular expression search. search for:

[^a-za-z][a-za-z][a-za-z][a-za-z][^a-za-z] 

it'll search for:

[non-letter character] 3*[letter character] [non-letter character] 

edit: said, wanted search numbers too, how:

[^a-za-z][a-za-z][a-za-z][a-za-z][^a-za-z]