How to delete line doesn't contain special word

[thongstx]

I have list, i want to delete line without @
Ex:
Abc@gmail. com
Achinas
SJklkj@China .com
dhakj @gmail.com
Chinamama

To:
Abc@gmail .com
SJklkj@China .com
Hello@gmail. com
Help me with code find and replace. thks bro.

[rcopat]

You can do this using regular expressions. In Windows, press Ctrl + F, turn on regular expressions by pressing Alt + R, and then type ^[^@]+?$. Then, press Alt + Enter to select all the matches. Finally, press Ctrl + Shift + K to delete those lines.