Why so many draws??????

I play on a  PC core i5 7th gen., dell inspiron 15., model 5567, 8gb ram, many tournaments all against all, 3 or 4+2 or 5 min games.
hash 64, 128 and 256....
opening book HS 7 moves, ctg.; 3,4,5 tablebases sszizigy
And the round robin tables are full of draws!!!????
Some times any engine wins....
The engines: Corchess
Raubfisch, CiChess, CF_ext, Stockfish Polyglot,  Brainlearn, Cfish......and other ones....

Why is that????
Pls help me and explain what i am doing bad....
Thx

If you dont want many draws, try to modify the Contempt parameter. Value 40 may solve it.

not what i want or what i dont.
I wonder why they cannot win each other ..... Are they the same engines or with the same strengths??????
I wonder why the different authors insist in going ahead with their projects if they are not capable to improve their force.....
did softwares do their best altoguether????
Thx. a lot!!!!

@Waldemar wrote:

If you dont want many draws, try to modify the Contempt parameter. Value 40 may solve it.

@Powerchess wrote:

not what i want or what i dont.
I wonder why they cannot win each other ..... Are they the same engines or with the same strengths??????
I wonder why the different authors insist in going ahead with their projects if they are not capable to improve their force.....
did softwares do their best altoguether????
Thx. a lot!!!!

@Waldemar wrote:

If you dont want many draws, try to modify the Contempt parameter. Value 40 may solve it.

Their strength is nearly same and they are playing too well to lose badly. Better the engines play, closer the results tested.