According to Hindu philosophy, if we could somehow found the right combinations and permutations of just 33 sounds, all the people in the world could understand one another, no matter what language they grew up speaking.
I think this may be the one of the reasons why small children learn languages so quickly. It would be good if linguists would explore this further.
Now, in the case of what I do, I don't bother with generalized vocabularies. I just stick to place names, tribal names, religious terms, and forget about the rest. If these place names, etc., have equal functions in the languages being compared, I conclude that the people speaking those languages have a common origin.
Here's an example, In Kerala, India, there is a god named Ayappa. He fought a battle with some decapitator demons named Mahesh-Asura. After winning the battle, he disappeared.
Now, in South America, among the Moshica or Moche, the god was Ay-apa Ek and a corresponding decapitator demon. Well, the words Moshe or Moche are similar to the Mahesh in India. In Sanskrit, Ek means "one; first." Therefore Ayappa Ek would mean Ayappa the First. However, in this case, I used my private system of linguistics: If it has the name, it must have the game. If it has the game, it must have the name.
But this is not all. There are other correspondences I considered when deciding that these Moshica or Moche were from Central India. Lord Ayappa defeated the Maheshasura on the banks of the holy river Pampa. The holiest river of the Moshica was also the Pampa. I have not yet mentioned the other similar correspondences. I felt that I was right in assuming that India's Lord Ayappa and South America's Ay-apa Ek were the same deities.