Hi there!
Dogs can make some weird noises and it can be difficult to tell if they're normal or a sign of sickness.
This is a link to a video of a strange noise dogs make called "reverse sneezing". Dogs can sneeze two different ways. Like regular sneezing, we don't worry about it unless it is associated with other signs of a respiratory infection, such as green nasal discharge or lethargy.
https://www.youtube.com/watch?v=1UyBrb0HhpkIf Hazel's cough-sound is associated with playing or getting excited, it may be a sign of something called a "collapsing trachea". This sounds a lot scarier than it is and can usually be treated well with oral medications, though extreme cases may require surgery.
Sometimes coughs and snorts can be underlying signs of chronic bronchitis or heart disease as well. Usually in more serious disease, we are seeing the signs associated with the animal not feeling well for days at a time, instead of just a single cough incident though.
I would recommend trying to take a video the next time she makes the sound and seeing if there are any common triggers for it. That information would help your vet give you the best answer as to what is going on.