Need ALL tips on ways to increase pregnancy.

J
So I have a 2 year old now. It took me 2 years to get pregnant. He wasn't planned but my body even while ovulating and having my guy cum inside I won't get pregnant...
Have any of you bought Pre-Seed or any vitamins to help conceive besides tracking your ovulation ?
Diet, exercises? Laying down with legs up? Haha 
I need ALLLLL the tips I can get. My man gets back from Germany 🇩🇪 next week around the time I'll be ovulating, and extra horny. 
He has cum inside of me twice already and Nothing.