Hello Anish, and welcome to the forum. If you want to reduce travel costs, you should visit mountains close to Lucerne, such as Pilatus, Rigi or Titlis. Even with such a short stay and relatively short trips, a Swiss Half Fare Card (allowing you to buy 50% discounted tickets) may be worth your money. I can't tell for sure though, as it depends on your exact travel plans whether regular tickets or Swiss Half Fare Cards will turn out to be cheaper. So you can best first decide what you want to see, and then calculate which option is best. The timetable allows you to search for connections and prices.