How to find videos that have free reuse license types on the web?
You can do this is on YouTube by adding a filter under the "Features" header. E.g.:



Also found that Vimeo offers similar search functionality when you add filters on the right:


Specifically on Vimeo these each mean:


CC0: Public Domain Dedication
CC BY-NC-ND: Attribution Non-Commercial No Derivatives License
CC BY: Attribution License
CC BY-NC-SA: Attribution Non-Commercial Share Alike License
CC BY-NC: Attribution Non-Commercial License
CC BY-SA: Attribution Share Alike License
CC BY-ND: Attribution No Derivatives License