xargs with multiple commands

xargs with multiple commands

In the current directory, I'd like to print the filename and contents in
it. I can print filenames or contents separately by
find . | grep "file_for_print" | xargs echo
find . | grep "file_for_print" | xargs cat
but what I want is printing them together like this:
file1
line1 inside file1
line2 inside file1
file2
line1 inside file2
line2 inside file2
I read xargs with multiple commands as argument and tried
find . | grep "file_for_print" | xargs -I % sh -c 'echo; cat;'
but doesn't work. I'm not familiar with xargs, so don't know what exactly
"-I % sh -c" means. could anyone help me? thank you!