Does The Intake Of Folic Acid And Vitamin Tablets Increase Sperm Count?

I had a semen analysis and found that my count was 4M/ml with motility 40, and morphology 70. Dr said my count is low. I lead a healthy life with no smoking, drinking and rugs, with vegetables as my primary food. I had also recently started taking folic acid vitamin tablets. Any chance I can improve the count. We have been trying to have a baby past 4 months. I am 37 yrs old and my wife is 31.5 yrs. Thank you.