It sounds similar to kaffir which is a derogatory term used in the Middle East for people who don’t practice a certain religion. It is also used in South Africa in a manner similar to the n-word in America.
As an actual Hindu who has lived in a Muslim majority Middle Eastern country, I'm not the tiniest bit offended, because a fermented yogurt drink happens to have a somewhat similar name as an insult based on religious bigotry..
Maybe people don’t spoon feed you explanations because you’re rude even to the people who try to explain.