Visit Gimmelwald from Lucerne?

Your questions are a bit hard to follow, beginning with your title question. You might consider revising that to reflect the actual point of your questions.

I'm not clear on the location of "vernassa". Could you clarify?

To answer your last question, it would be much better to make a day trip to Gimmelwald from Lucerne. It's a fairly short train trip from Lucerne to Interlaken Ost. From there you'll have to take the Berner Oberland-bahn to Lauterbrunnen and then use one of two routes to reach Gimmelwald. If you're only going to see Gimmelwald, use the Post Bus from Lauterbrunnen to the Cable Car station and Stechelberg (about 20 minutes) and then take the Cable Car to Gimmelwald. While there you can either hike uphill, or take the Cable Car to the scenic town of Mürren, which is just above Gimmelwald.

Ken, don't you think you think they might be referring to Vernazza, Italy, in the Cinque Terre.

Is your "caps" key is broken?

Gimmelwald is in the Berner Oberland. It will take about 3 hours each way to go from Lucerne to Gimmelwald. Not a day trip. Plug your ideas into Rome2Rio. Note you can do multiple legs. See what the travel time estimates are.

Lee,

That thought occurred to me, but rather than guessing I felt the quickest solution would be to ask the OP for clarification.

I've done a day trip from Lucerne to Wengen so it is very douable in a day. It is a very senic trip so the time pases by fast. Combining Gimmelwald with you trip from Chiasso would probably be to much for one day.

Three hours each way. You can get a round- trip same day ticket for 79CHF, but you have to use the same route in both directions (train to Lauterbrunnen, bus to Stechelberg, and cablecar up from there).

If you do mean you are coming from Vernazza ( not Vernassa), that is a very long trip, so not a good idea to head to Gimmelwald on the way ( since it is not on the way). But a daytrip from Luzern might be nice if you don't mind the long journey ( it is quite scenic).