How to model Chemical Kinetics when both ligand and receptors are moving?

I am not a chemistry student but trying to understand something that requires Chemistry. My problem is that when we have Ligand and receptor reaction to form complex we normally assume as [from wikipedia](https://en.wikipedia.org/wiki/Ligand_(biochemistry))


"In protein-ligand binding, the ligand is usually a molecule which produces a signal by binding to a site on a target protein."


My issue is do we have chemical kinetics giving us some clue when both of Ligand and receptor is moving, of course this is something like a reaction in a solution but **I am majorly concerned with probability that Ligand be able to bind with receptor when both of them are in random motion and any literature related to that.** 
I may not that much clear in my presentation, but it will be really helpful if any kind of support be given.


