If you would like to publish your student note or comment, you'll need to ensure that no one else has beat you to publication on your exact topic. This process is called a preemption check.
A preemption check should come relatively early in your writing process. Once you have a good idea of what you'd like to write, but before you've done significant or substantive research, you should check to see what other authors have written on about your topic. Google Scholar is a good tool to use to search for published articles on your topic. For writing in legal academia, check Lexis, Westlaw, and HeinOnline. For writing that touches on interdisciplinary topics, you should expand your search to subject specific databases. You can view a list of the non-law databases available to you through LMU here.
Database searches will return results for published papers or articles, but you should also pay attention to forthcoming or in-progress articles. SSRN is a useful place to check.