Dmitriy, I understand your frustration. I have some things to say, but I don't know if they will help. I work as an illustrator when the project interests me. I am in the US.
What you are seeking is not simple at all.
What you try to do here may, in fact, not be possible. You are a single person, with no credentials, reaching out from a country that does not have a good reputation when it comes to respecting artists' rights. From there, you are reaching out to a country that does not have, itself, a well-developed market for producing and selling the kind of work you want, and where you cannot communicate directly due to the language barrier. (In fact, it's more than a language barrier. Your intended market doesn't even share a common alphabet.) Also, are you clear in what you say you want from the artist when you reach out? Do you want to buy existing work for reproducing? Do you want to commission custom made illustrations? Do you have an illustrator's brief for them to see? Either way, there are lot of complex considerations for the artist regarding copyright, regarding how he or she will be able to work/communicate with you, regarding how the artist can protect self from a bad outcome. I think it easily could be seen as too much trouble and risk.
If this is the case, are you so determined to have an Asian artist, preferably a native Chinese artist, do your illustrations that you would rather give up than make another choice? Up to you, of course. But before you do, maybe try this: ask your existing artists, Norwegian and Mexican, if they know anyone (anywhere) who could produce what you want. They know you and they know you are reliable. They can be your reference to a satisfactory artist. Be warned that it will difficult to find an illustrator who works in watercolor, and anyone who does will likely be very expensive. That's because watercolor painting is a technically difficult medium for an artist who primarily works on demand to a deadline.
But if you don't want to be flexible at all in your requirements, I am afraid you may indeed have blocked yourself.