thats not it

Any one of the following:

そうではない
そうでは無い
そーではない
そーでは無い

"...sou de wa nai"

"...that's not it."

Catchphrase of Kishin Sagume from the 15th cardinal Touhou game. Sagume says this during Sanae's route every time Sanae makes an incorrect guess about why Sagume isn't speaking. Can also be interpreted as "that's not so" or "it's not like that".