Silva insists his team's progress is stalling due to the sales of talent like Joao Palhinha, who left for Bayern Munich last summer.
“Our object, even losing players, is always to have better results and to achieve better things,” he said.
“You can lose important players, we can sign new ones that can be more important players in the future for us, and that is the most important thing.”
Silva admits having to plug the holes and start again is frustrating.
“That is reality. If I’m not frustrated or not, I’m not going to change it. I cannot change it.
“In some moments, even if I would like to keep all of them and improve, to reinforce the squad, that is the reality of the club. We have to look at it as a challenge — no more than that — don’t cry about it.
“Okay, we have to find solutions. The club can take steps forward quicker if we don’t sell players, but that is the reality. We must find solutions.”