Find all files (type f) in the current directory and its subdirectories (maxdepth 2) and execute the awk command on them. The awk command will randomly select one of the files and print it, then randomly select another file and print it, and so on.
find ~ -maxdepth 2 -type f -exec awk 'BEGIN { srand(); o = int(rand() * 5.999) + 1 } o && o-- || { print $0; o = int(rand() * 5.999) + 1 }' {} +