I tried searching, but couldn't find anything. What's that sound called, the one you make when you purse your lips and make that kissing kind of sound? I guess people make the sound in different contexts, but for example:
Person 1 does all sorts of complicated things to accomplish a task, Person 2 does it easily. Upon seeing Person 2's method, Person 1 may make this sound.
If there are any Kannadigas, in Kannada it's called lochhguttodu.
Best Answer
Are you thinking of tsking? I realize that the action isn't the same, but I'm not sure there is a separate word for the specific mouth noise you're describing.
Perhaps raspberries, as in to blow raspberries: