It is easier to think of the translations of these phrases in formal (or correct) English.
En lo que As far as
Con lo que with that which
Para lo que for that which
de lo que of that which
Por lo que because of what
a lo que to that which
And don't encourage bad English. "You can never place the preposition at the end of the clause like in English: Be careful what you wish for." You should never end with a preposition in English Be careful of that which you wish or Be careful for what you wish.