Meadow hay is as a rule a mix of various types of grasses. The composition varies, but pretty much any grass hay is good for rabbits. Unfortunately theres no telling what a bun likes or dislikes until you’ve tried 😬 Alfalfa (lucerne) is a legume hay and best avoided with adult buns, since its rich in both calcium and protein, but its great for buns under 7 months of age.
Orchard grass is a specific type of grass, dactylis glomerata. I doubt it grows in Indonesia, since it doesn’t in Australia – its a cold climate type grass.
I use a very soft mix of grasses called Vita Verde, Alpenwieser Hay. I looked online, it might be available in Indonesia? It has a lovely, herbal scent and its they only type of hay my bun really likes. (Here it’s among the cheapest types of hay, but I’m guessing pricing could be different in Indonesia).
Its probably very wise to not serve hay soaked in water, since you are in a very warm country 🙂