Original research refers to scholarship written to expand a field of knowledge. It usually involves experiments and observation, answering a question not addressed in the field. Sometimes referred to as primary resources, original research is the first place the study has been discussed.
Review Articles are discussions of the state of the field at the time the review was written. For example, climate change scientists in 2017 want to know about studies of sea ice in the past twenty years, so they can avoid duplicating studies, and so they can position their own work to make a meaningful contribution to climate science. Review articles discuss many different studies, explaining how the field has changed, what areas the field has addressed thoroughly, and what areas of study are still missing.
A librarian can help you refine your search results to one of these.