distributed lag model approach

Hey
I want to analyse the causal relationship of chinese FDI on the commodity import from African countries using a distributed lag model. So the hypothesis would be that an FDI inflow in year t has a positive relationship with commodity import of china from that particular african country in the following years t+x. I'm interested in how you would approach this analysis particularly regarding dummy and control variables. How could one create the dependent variable "commodity imports" (metals, ores, minerals, oil/gas).
Thanks in advance for your help!