Cultural misunderstandings generally refer to incidents in which differences between one's own culture and another culture leads to some kind of mistake.
In Ukraine, people often speak while someone is talking. They say simple things that in English would be like "Yes." "Okay." "I understand." etc. This lets the speaker know that the listener is following. However, in English, this is often the opposite. If someone keeps saying "Okay." or "Yes." while you're speaking it's a sign that they aren't really listening or that they aren't very interested in what you're saying.
So if a foreigner travels to Ukraine, Ukrainians may often repeat "okay" or ''yes' and such to let them know they are following. They expect to hear that, but because of the differences in culture if the foreigner isn't familiar with this specific part of the Ukrainian language it can lead to misunderstandings.
This is a fairly simple misunderstanding, but there are others that can have greater consequences of course. The best way to avoid misunderstandings is to learn about and be respectful of another countries culture while you're there.
