But though he had done so many miracles before them, yet they believed not on him:
Even though He had done so many miracles before them (right before their eyes), yet they still did not trust in Him and failed to believe in Him–
But though he had done so many signs before them, yet they believed not on him:
Jesus had done many miraculous signs before the people, but they didn’t believe in him.
And although he had done such great signs in their presence, they did not believe in him,