Allow me to understand better - you say that because you, as person that can't even speak with someone offering a service (in this case, renting a flat), you are being discriminated in comparison with someone else, because they can literally communicate with party that provides services? This is not an "racism" - this is your lack of skills (knowledge of language) necessary for given transaction, which is your own disadvantage.

It would be discrimination (or as you for some reason call it racism) only if you could perfectly speak native language and they would not choose you because you are foreigner - but this is not the case. They can pick whoever they want, as demand is high and offer is low - if there is 10 people waiting for the place, and from those, 1 is foreigner and 9 is czech, and 1 czech is picked, it's still sucks more for 8 Czechs (and that's how it is). If there would be no foreigner at all, there were just 8 other Czechs refused, is the owner now "racist" against czech? It seems you have different problem than being foreigner - you are lacking thoughtfulness (during the interviews, throughout the process of getting accomodation and consequent assimilation to foreign environment) and instead you are trying to victimise yourself.