Growing Vegetables In Containers I Am New To Growing Vegetables And Would Like To Know?

I am new to growing vegetables and would like to know? - growing vegetables in containers

I have three tomato plants and a jalapeno pepper plant growing in pots. They grow fast and tall, but produce smaller tomatoes and jalapenos. Should I prune these plants in the hope that produce more? Other proposals that could give me would also be helpful. Thank you.