it's not always the gift item that counts, but rather it's first-class or luxury brand name. To bring 'Canadian Club' whiskey from Canada is you're Canadian would be well received as would something connected or specific to your home region, etc. Something that is either very difficult to find or extremely expensive in Korea is another option. If you're bringing the gift from another country and are not aware yet of what is hard-to-get here, best to bring something associated with your home country/or where you've purchased it or a high end luxury brand.