If you want to search a particular line in multiple files, you can use following code.
grep -r "abc cde efg ko is" /path/of/file1 /path/of/file2
It will give you the lines with file name where searched text is appeared.
If you know the directory but you do not know the files where text is appeared then grep -r
will do that for you
grep -r "abc cde efg ko is" /path/of/directory1 /path/of/directory2
Now it will list the files with searched text where the text abc cde efg ko is
is appeared in the files of these two directories,
In above example, it will search text abc cde efg ko is
in all files of directory1 & directory2 and display a list in the output.