United added just three new players this summer, with Harry Maguire, Aaron Wan-Bissaka and Daniel James joining for a total of £145m.
Asked if they had the resources to further add to their squad, Solskjaer said: "There is money available when there are the right players available.
"It is not about a quick fix, it is about a longer rebuild. It is not time to change that attitude when you haven't got the correct answers from the players you wanted.
"When the transfer window closed there was a feeling of relief. I am delighted with the three that we have signed."