grep with multiple keywords need some knowledge of regular expression. But that is not difficult, use (OR).
Let say you want to grep “me” and “you” at world.txt, you do
grep "me\|you" world.txt
You need to put ESCAPE STRING ( \ ) for OR ( | ), else it will treat it as a simbol you want to search instead of regular expression symbol.
You can do this:
grep -E "me|you" world.txt
-E treat symbol as regular expression instead.
egrep "me|you" world.txt
Simply use egrep for regular expression grep.