Cross race effect is a documented psychological condition that has been studied for decades. It has been proven in hundreds of studies that people are poor at distinguishing faces of people from other races unless they have a fair amount experience with the race. If you have never been exposed to Chinese people in your daily life, you will perceive them to be similar. This is not you being racist or bigoted, this is just you being human. As you gain more and more experience with the different race, this effect will wear off.

I am from India. North East Indians share a lot of facial characteristics with East Asians. Consequently, I never felt that Chinese people or Korean people look similar but most of my Indian friends in China felt this for about an year till they gained enough exposure to notice the differences. Cross race effect has two theoretical explanations.

Firstly, when we spend time with people of our race in our formative years, we develop an expertise in recognizing them using traits that differ in variability. If you are white, you usually use hair color to distinguish between two strangers. I as an Indian use the shape of the hair or the skin tone to do so. When you are exposed to a different race, you need time to internalize these distinguishing features. Till then, you will feel that they all look similar.
Secondly, cross race effect is also explained by the age old fundamental tenet of behavioral psychology, that humans are cognitive misers and try to minimize cognitive overload by simply ignoring things. When we see someone from a different race, to minimize cognitive overload, the added weight of thinking and noticing the minor facial features that differentiate us from them, we just recognize that we are different from them and ignore the minor characteristics. 'They All Look Alike': The Other-Race Effect

I suggest you spend more time with Chinese or Korean people, talking to them, hanging out with them to give your mind more time to internalize the facial characteristics that distinguish them and in due course of time, this effect will wear off.
This brings me to, 'Why do all those Korean women in that image look similar?'. It is unfortunate that this image from Miss Korea went viral for all the wrong reasons and the real reason why these women look similar was lost somewhere in between, that 'Because they're a bunch of photoshopped women with the same hair color'. Andy Lee Chaisiri's answer to Why do all these Korean women look so eerily similar?. I quote from Andy's answer above,

*And here's what those contestants look like without all that photoshop:
Each an individual


They look similar to each other to you and me because we've spent very little time around them, and so our brains haven't learned to differentiate between people with Chinese features. In fact, they are as different from each other as children anywhere else; we simply don't notice the differences.

The same is true in reverse. Chinese people who have spent very little time around, say, Americans, have a hard time telling them apart, although the global spread of American movies probably gives non-Americans more familiarity with them than most Americans have with people from other cultures.

We even see this psychological effect happen with animals. Most of us think most chimps look alike, but to scientists and zookeepers who spend many years with them, they look as different from each other as people do. It takes time and immersion with unfamiliar people, animals, and objects for our brains to notice differences between them.

They don't. I can tell Koreans from the Chinese, because I am Chinese myself, and I know enough Koreans to tell a difference.

Facial recognition is an ability trained and learned over the course of one's lifetime. Thus, if you have little exposure to Chinese/Koreans, you have poor ability in distinguishing them. Similarly, a Chinese person who has not been exposed non-Asian people find it difficult to distinguish between white people.
Another example of this would be: we typically find all chimps in the zoo to look the same, but a person who has spent time with chimps, such as the worker in the zoo or a primate biologist like Jane Goodall, could easily distinguish them.

It's a matter of familiarity. Humans have evolved to distinguish what's around them. So if you haven't been around many Asians, they look rather similar, but once you spend time there, your brain will learn to notice more of the subtle differences (all faces are only subtly different but we are used to having to distinguish those of our own group).

https://www.quora.com/Why-do-East-Asian-people-look-alike