jiè​tí​fā​huī

to seize on a theme

借题发挥 借題發揮 jiè​tí​fā​huī
to seize on a theme
To use the current topic or a specific incident as a pretext to express one's true intentions or personal views; to make a fuss over something to serve one's own agenda.

Frequency

Movie subtitles
0.060 per million appears in 0% of films
Written text
0.454 per million

Sources