title: Search for files containing specific string in text file in unix
body: <p>i am new in writing a shell script and would like to search for a specific string in files with extension "*RETURN.DAT" in a directory. the strings i want to look for are in a separate file. what unix commands should i use? i am mixed up using find and grep. i also need to copy the files i found in another directory. thanks in advance.</p>