Please share summer vacation or winter break you are asking for because any certification and diploma course will be of 3-6 months but DU also offers few short term courses like Effective Communication and Personality Development through theatre,Medical Nutrition Therapy; Food Safety; Energy and Technology, Financial Management; Media Studies; Airlines, travel agent and airport handling; Interior Designing; Corporate Communication and Public Relations; Courses on Entrepreneurship; Effective Communication and Personality Development; Foreign languages: French, Spanish and Russian,English Language Proficiency Course; Personality Development; Yuvodaya- Metlife Initiative; ICICI Foundations of Banking Course (for pursuing these courses one should be the student in UG courses of Acharya Narendra Dev College; there is no extra fees and no fixed duration) etc. So as per your interest and convenience you can take admission.

Also, you can go through the below link -

http://col.du.ac.in/course.php

Good Luck!!!