# I stored the text of your original message in "Sans titre.rtf"
set theFilePath to (path to desktop as text) & "Sans titre.rtf"
tell application "TextEdit"
open file theFilePath
set theText to text of document 1
end tell
set listOfFileNames to {"comfortable", "TextEdit", "Yvan KOENIG", "Weisbin"}
set foundNames to {}
repeat with aName in listOfFileNames
set aName to aName as text
if theText contains aName then set end of foundNames to aName
end repeat
foundNames
--> {"comfortable", "TextEdit", "Weisbin"}