I want to combine two day-trips by going from Amsterdam in the morning to Keukenhof, then mid-day on to The Hague. Then early evening Hague back to Amsterdam. Any suggestions on which buses/trains to take? The Keukenhof combo tickets are all round trip.
If you look on the Keukenhof website, there are options for getting a single ticket with or without the entrance ticket. https://keukenhof.nl/en/ov/#faqcombitickets
You can also use the Netherlands public transport app to plan your journey - https://www.ns.nl/en