If you are trying to track down the contents of this archive or locate the specific paper it refers to, try these steps:
In many student psychology documents and course notes, the citation [EYS94] or [CITATION Eys94] is used to reference the widely used cognitive psychology textbook by Michael W. Eysenck (specifically editions published around 1994).
Look at the reference list of the source document you pulled this from to see if "EYS94" is listed as a short-hand citation.
Look at the webpage, syllabus, or folder where you saw this filename mentioned to see if there is an author list nearby.
Could you provide the or the context where you found this file name so I can narrow down the specific paper you need?
University students and professors often compress lecture notes, PDFs, or scanned book chapters into .rar files and name them using the author's initials and publication year (e.g., Ey senck, 19 94 ).