My SO wants to help

So my SO and i have been told that we have unexplained infertility... I’m currently on my second round of Clomid... My SO last night was talking to me... He asked when could we start trying again ... And said... He wants to start taking something to maybe aid in is part... Something to help his swimmers out... Have any of you ladies found something good that may help improve his sperm... I’m very blessed to have a fella that wants this as much as I do...