It's possible you are thinking of a different song, perhaps one from the English dub of the anime, or a fan-made song.
Could you provide more information about the song you're looking for? Esimerkiksi:
* Which version of Sailor Moon are you thinking of? (Alkuperäinen japanilainen vai englanninkielinen dubaus?)
* Mitä sanoituksia muistat?
* Tiedätkö, mikä hahmo sen laulaa?
With more information, I can help you identify the song!