То холодно, то жарко

Missing, extremely new, or very obvious to obtain.

The Chinese title, 忽冷忽热, which roughly translates to hot and cold. The phrase means being calm at one moment and emotional at another. It comes from 读书杂谈, from an excerpt that translates to: "Research requires reason and calmness, while creation requires emotion, or at least some passion. So I get hot and cold and feel dizzy."