There are five languages in Google AdWords that you can uniquely target by their characters; Greek, Hebrew, portions of Japanese, Korean and Thai.
From April, if you’re targeting any of the above stated languages, your ad is eligible to show for all queries in your chosen language that match your keywords. This is regardless of your interface language. However, your location targeting settings will still apply.
So, if you have the keyword “τσεισκέικ” (Greek for “Cheesecake”) in a campaign that targets the Greek language, your ad will be eligible to display whenever a user searches for τσεισκέικ. This will occur, even if the user’s interface is in English.