Ashamed! 50

The author repeats many times as necessary to read or even that "words fly away, written words remain" and yet this book is riddled with spelling and syntax. A mistake from time to time, it is forgivable but when there are so many that reading becomes annoying ...
Additionally, errors on the bottom are also numerous. I am not a specialist in all areas (otherwise I would not have bought this book) but I can not help but notice large and damaging errors for the credulous reader follows some advice. So what about for the correctness of the information I previously did not know ?!
In summary, I give up reading this book for lack of confidence, and I recommend very strongly.
Is it a book for dummies or dummies ?!