The phrase "to investigate this phenomenon" means to study or examine this unusual or interesting occurrence in order to understand it better. Full definition
In this activity you will investigate the phenomenon of apparent motion by making your own flip - book animations. (scientificamerican.com)
It was a bit of a mystery to the scientists investigating the phenomenon: a brain disease driven by the death of specialized neurons was strongly linked to exposure to a particular pesticide. (sens.org)
Maybe we can design a machine to measure the body's energy and then we'll know something empirical about the subtle body — because that's how we think about investigating phenomena. (yogauonline.com)