Search for Text with `grep`

This lessons seems to break at the beginning of the video.

I am trying to grep a variable which is the output of a find command. I'm getting permission denied from the grep, but if I pass the same file directly it works. How could I solve that?

var=`find . -path ./node_modules -prune -o -path ./public -prune -o -type f -name "*.scss" -print`
grep "string" `$var`

Any tips?

Strange, the grep command is only showing me 1 or 2 results when I invoke it on a keyword list with tons of results. My Keyword text file has hundreds of results containing what I invoke grep to find in it though. How could that be?