It is operative income from which they pay taxes to Germany if they pay taxes to Germany. Taxes from revenue related things are paid to Czech.
Revenue is what they get from selling cars they make, operative income is profit that they make from those sales. Difference goes to salaries, sales taxes, components/materials, etc. from which taxes are paid to Czech and which generally increase Czech's economy, as most of the cars they make are exported out from Czech, which means that those sales bring more money to Czech's economy. So that money mostly goes to Czech, although they may buy materials/components from China or some other even cheaper country, as for example Czech trade deficit with China is only little bit less than their trade surplus with Germany. By looking numbers alone you could make simplification that it is like taking money from Germany and sending it to China.
Trump thing is because he just happens to talk about how similar situation is bad for USA, US companies produce goods, like cars, in Mexico and then bring them to be sold in US, meaning that he sees that it benefits Mexico.
Why are tax heavens than so popular if you are obligated to tax where you originaly created product which you sold much more expensive somewhre else?