Can I travel after filing application for naturalization?

Filing an N-400 application really puts no restrictions on overseas travel as long as you continue to qualify for citizenship.  As I always say, keep a good record of your trips after filing and when you go for the interview, just in case you are not asked about it (most likely the officer will ask about trips or ask a general question if anything has changed -- people get divorced, a spouse dies, jobs change, etc.), you should volunteer the information, preferably typed on a piece of paper following the same format as the application, of course with your name and A#.