Other than classical music stations, my Czech husband's favorite radio station in Czech Republic is called "Radio Blanik". All Czechs know this station. You can hear songs from there by visiting
Radio BLANIK and the clicking the round red button all the way on the left middle of the screen. Most songs are in Czech, with the occasional ones in English. When there is a song in English it's usually a song that never made it to the United States. I find a lot of these Czech songs a bit cheesy, but some are good. Sometimes they are American or British songs sung in Czech. When they are, they sometimes modify the lyrics a little in order for it to work with the music.
A few weeks ago my Czech nephew and s-i-l were humming "Hard Day" but to the music of the song "It's A Heartache" by Bonnie Tyler. I told them that the original song did not include "hard day", but "heartache". My nephew didn't believe me, at first, so looked it up. [He's a little cocky that way.] I had to explain the meaning of "heartache". Turns out that the word in Czech is "žal". Would have been hard to work that in well. Or if you literally google "It's A Heartache", it translates to "Je to bolest srdce." which means you literally had a heart attack. As for the use of "hard day", it's common for Czechs to incorporate a few words or phrases in English, but the rest in Czech. Clearly they thought "hard day" would be more widely understood and a good enough deviation for translating.