What is wrong with 'další věc'?
I would add that while both jiný and další can mean "other/another," they are slightly different. The sense of jiný is "different" and the sense of další is "next/additional."
it means "the next thing"
which would be different. :-) ha ha but I get the distinction
How do you do accents
Download a Czech keyboard for your device. Use your favorite search engine to find out how to do that, if your device doesn't have an easy-to-find setting for adding keyboards.