find . -type f | xargs file | grep text | cut -d\':\' -f1 | xargs grep -l \"TEXTSEARCH\" {}
it\'s a good solution? for find TEXTSEARCH recursively in o
If you know what the file extension is that you want to search, then a very simple way to search all *.txt files from the current dir, recursively through all subdirs, case insensitive:
grep -ri --include=*.txt "sometext" *