"Further experimentation" means doing more tests or research to gather additional information or evidence in order to gain a better understanding or to reach more accurate conclusions about a particular topic or problem. Full definition
Oh, and the perfect night for further experimentation with Chambers at CB. (justarsenal.com)
Further experimentation led the researchers to conclude that the surface protein is, in fact, an early player in the cellular cascade that leads to eye formation. (scientificamerican.com)
But the flavor was amazing, so I knew it was worth further experimentation. (alidaskitchen.com)