i have a some years old account with adsense, but i can't see any option there for Themed Units. or is there someway else?
The Themed Ad Units are specifically tailored to users in the appropriate locations as determined by their IP address. For instance, a user in the United States might see colors and graphics appropriate to the Fourth of July while users everywhere could see colors and graphics for New Years Day. Again, it’s your choice and your page. You can turn Themed Ad Units on or off by yourself. Just log in to your account, go to the My Account tab. On the Account Settings page, scroll down to the Ad Type Preferences section and click Edit. You can now enable or disable the Themed Ad Units.