Bittersweet

Question

my vine has only produced 4 berries the vine itself grows well but does not produce

Answer 1

If the vine has very few flowers, see this article for possible reasons why:
https://www.gardeningknowhow.com/plant-problems/environmental/plant-not-blooming.htm

If it produces flowers but very little fruit, it may be that the flowers are being damaged by high temperatures, insect infestations, or stressful environmental conditions.