Ruslan, why did you change the original. There’s nothing wrong with it: “During the Clinton presidency, Hilary was often viewed as the tail that wags the dog.”

This is an idiom that means that someone with seemingly less power controls or influences someone in a position of power or leadership.

the only result was in that form

Look at my example))

TAIL WAGGING THE DOG is a situation; THE TAIL THAT WAGS THE DOG is a person