I’m not sure what filter you used (maybe a polarizing or UV filter?). You’ve also turned down the exposure setting which has allowed you to enhance the blue in the sky. However, I notice a theme in your photographs. You aren’t using “layers”. All of your attention is placed on one depth. You don’t use the three layers of space.
In your next sequence of photographs I want you to try to add layers to your photograph by having objects in your foreground, middleground and background. Right now your photographs are a little “flat”. You can easily change this by using layers to create depth. There is a great article here I want you to read.