If you have multiple experiences within the same project that are in the same state, then only one will be delivered to the page for any given user. This is determined according to the priority weighting.
To change the weighting, go to the panel for any experience in the Experiences screen:
Simply drag and drop to reorder.
Whichever experience is prioritised first will have it's audience condition checked against the user first. If the user does not match audience criteria, the second, third.. etc, will be evaluated in turn until a match is found.
How do I create multiple experiences in one project?
You can create multiple experiences in a single project either from the Experiences screen, using the "Clone Experience" functionality, or from the Experience Create screen by selecting "Existing Project" from the Project Details section.