Solution for the combinations

The question was "How to take advantage of White´s uncoordinated pieces?".

1...Qe1!
2. Nd3 (or 2. Nf3 ; 2. Nc4 )
2...Qe6!

...and in the best case White would lose a piece.
Only this solution is the right one. There are few more interesting continuations, but only this leads to winning advantage for Black.

In this example Black has an idea to take on a2 with a mate on a1, only if White has not safe square on d2 (in the case of Bxc3).

1...Nxe4!

Not 1...Qxa2 2. Bxc3 and now it is not possible to play 2...Nxe4 because of 3. Qxg7#

2. Bxc3, Bxg5+!
3. Bd2, Qxa2
...and Black wins.

In this position Black has perpetual check with his queen.
If it is White´s move than he/she would mate with Qh8#.
White´s queen is actually a weakness and Black can take advantage of that with a nice combination.

1...Qxh6!!
2. Rxh6, Rxc1+
3. Kh2, Ng5!

Black will win a queen for one of his minor pieces and stay with a piece up.

In this example you have to be very precise.
There are many candidate moves (and ideas), such as Ng4, Rg8 and Qe1+ but only the right combination of these moves is the right solution for the combination.

1...Qe1+!
2. Kxh2, Rg8!

As simple as that, but at the same time very hard!
Only the combination of these moves in the right order can counts as the right solution.

This is a pure calculation exercise.

1...Rxe2!
2. Bxc5

If 2. Qxf7+, Kh8 3. Bf8 which is a very important variation, Black has winning resource 3...Nd2+ with mate.

2...hxg6
3. Qxe2, Bxb2
4. Qe8+, Kh7
5. Qxf7+, Bg7
6. Bd4 ...and Black has to take perpetual check!