Need Help Identifying Korea

Are these all south korea ? Also why doesnt the tiger stamp have KOREA written in english? Any idea whats the significance of that stamp?

Only some of the earlier South Korean stamps carry the country name on them in Latin script, and when they did it was usually "Korea" or "Korea Postage" . Later, they were inscribed "Republic of Korea" in smaller type.

The one that is inscribed "State of Kuwait" is from Kuwait.

South Korea can generally be identified, if they have the yin yang icon.

Yes, the first six stamps are from South Korea. Three of them say "Korea" and they all have writing in Hangul, the Korea script, as well as the Korean yin-yang symbol.

You ask why one stamp doesn't have the country name written in English, but not every country even uses the Roman alphabet let alone writing their country's name in the English language. We shouldn't assume they should do this. The largest populations in the world are in India and China, but U.S. stamp names aren't also written in Hindi and Mandarin. Well, you get the point.