As a father, what can I do to make my daughters happy if I'm working abroad?

My dad was working abroad too. Communication is the key. Whenever you're at work don't forget to talk to them and ask them about them so that when you came back you still know many things about them and also don't forget about their birthdays or any achievement then surprise them with a small gift or treat them somewhere. Lastly catch up whenever you're home. Always tell them how much you love them.