It sounds like you want to rephrase or expand that idea. Here are a few polished options, depending on what you need:
Clear and neutral
- Many people are unaware that the two buttons on a toilet cistern serve different purposes.
More explanatory
- Many people are unaware of the dual function of the two buttons on a toilet cistern, which are designed for different flush volumes.
Slightly more formal
- A significant number of users are unaware that the two buttons on a toilet cistern perform separate functions.
With brief clarification
- Many people are unaware of the dual function of the two buttons on a toilet cistern: one releases a reduced flush, while the other triggers a full flush.
If you want this rewritten for a specific context (school assignment, article, presentation, or exam answer), tell me the tone and length you need.
