Perez admitted to Real Madrid's partners at an assembly that the club had tried to sign Manchester United ace Paul Pogba in the summer, just as they have tried to sign Lewandowski in recent years as well.
"There are players who don't get sold," Florentino said.
"We went for Lewandowski for several years and nothing happened because he has no clause and they [Bayern Munich] won't sell him.
"There's no way. And that's happened with Pogba. When certain players can be sold, we can go for them."
Florentino also addressed the problems the club faced last season, and recognised that mistakes were made.
"We had nine Ballon d'Or nominees and a team valued at 1.2 billion euros," Florentino explained.
"Last year the problem wasn't one player, but everyone's mentality.
"Important players have been signed, [Eden] Hazard among them."