Don't push your luck
To try too hard to get a particular result and risk losing what you have
Lucky break
A piece of good luck that ends in success.
Thank my lucky stars
Feel grateful for someone's good fortune
Lucky streak
A serie of wins in gambling
Wish someone luck!
To hope someone is successful.
To be in luck
To be fortunate
Tough luck
Bad luck, sadly
Luck of the draw
The result of chance and something that you cannot control
String of good luck
Serie of fortunate events