To quote a good friend, "Errors in well edited books are uncommon."
If you want to improve your vocabulary the easy way, READ.
Read anything that is interesting to you.
Read a translation of a story you have read in your first language.
Because you are getting the "Transfer" I mentioned in a post on Wednesday, December 23, 2015!
Read for a short while before you go to sleep.
(It will help you to sleep and you can "process" the words while you are sleeping.)
Read for pleasure. Read what you enjoy reading.
Don't be shy about reading below your age level.
Today's Wiki Wiki one point eXpression is:
"Kill two birds with one stone."
To take care of two problems with one action.