Just make sure when you Jisho.org all your words, you make sure the ‘common words’ box is checked…. Other than that, any common word is fine to learn (you don’t always have to do this, but learning common words is a lot nicer… although I picked a few non common words because that was all there was to find what I had in mind)…. Personally, at this point in time, I have practically mastered my passion list so eventually you probably won’t worry about it as much…
Just pick words of things you have interest in etc.
An example of one would I did was 心理 — state of mind/mentality (related to psychology) because I have an interest in the mind and psychology.
Another example, 哲学 — philosophy.
Perhaps たたかい（戦い）– fight/battle would be a word which interests you? (rather common in ‘Attack on Titan’ ^^)
Good luck! (Also, if you have not yet, get rikaikun or that other addon similar to it…. :D 理解君！)

• This reply was modified 11 years, 6 months ago by  Yamada. Reason: hee hee hee