Collusion itself is not a crime and that is what you are stuck on. Collusion can lead to conspiracy and other crimes. When people collude to commit an unlawful act it is called conspiracy. Conspiracy is a crime.
The lies and the coverups are crimes. Whether 18 usc 1001, obstruction of justice, conspiracy to violate 11 cfr 110.20, You had Trump saying he had breaking news on Hillary, right after Trump jr scheduled the meeting with somebody hawking kremlin intel. And when the meeting went bust, so did Trumps announcement. Coincidence?