Thank you for the answers.
Some general comments:
1. настолько. Totally new word for me. It means "so" and is to give emphasis. For example why I cannot say Paul: Несмотря на то, что эти продукты не такие сложные
2. деталь. Until now I consider this word as a synonym of a "particle of mechanism". подробность for me is more closed to what I call detail. Also I don't understand when to use нюанс instead the other two words.
3. The expression deep knowledge I found it in google translate (глубокие знания) and as you can see it is a fixed term: Google Translate). But now I know that the correct is:
знать [что-то] в деталях, знать [что-то] во всех деталях
4. If I want to say: A person that wants to survive in a competitive word should all the time struggle to acquire new skills = Человек желающий выживать в конкурентоспособном(???) мире должен стараться приобретать новые навыки все время . Here приобретать sounds correct?
5. досконально is a synonym of подробно and nothing more
6. it-ogo when I listen the expression "так уж" and especially the word "уж" I feel that I am learning Japanese So I suppose is a synonym of настолько.
7. затруднительно: I like it.