" how to win friends " written by del carnegie

" 7 habits of highly effective people "

" monk who sold his safari "

" the secret " rhonda berna ( my favourite )

The Alchemist by Paulo Coelho 

I think it is called the monk who sold his ferrari:D

All the Names (Jose saramago )

Steppenwolf (Hermann Hesse)

Those books arent as motivational as The secret.

(writters arent telling you what to do to make your life better directly)

But they are related to purpose of life and,i am sure, will have positive effect on your life.