United Kingdom, Sept. 14 -- Seth Rogen has revealed the raunchy four words of filmmaking advice he still returns to after decades in Hollywood.

The 44-year-old actor, writer and director recalled receiving the naughty instruction from his longtime mentor Judd Apatow while making the 2007 comedy Knocked Up, during a career-spanning appearance at the Toronto International Film Festival.

Seth was speaking at TIFF's John Bassett Theatre before receiving the Norman Jewison Career Achievement Award, with the festival also screening two of his latest projects, Babies and Tangles.

He said: "At one time, when we were shooting Knocked Up, we would improvise a lot, and we were improvising and Judd screamed from the other room, 'Less semen, more e...