Boro have been linked with Norwich duo Dani Ayala and Luciano Becchio, as well as Leeds striker Ross McCormack, in recent days, and Mowbray is keeping his fingers crossed as he awaits a breakthrough.
He told the Evening Gazette: "We are working on things on a daily basis. How close are we to doing something? I would like to think pretty close.
"Let's wait and see what happens, but we are working very hard to strengthen the squad.
"The point I have been trying to make is we have a good team. I just feel the squad needs to be strengthened so that if we suffer an injury, we have cover in place."
Meanwhile, Nottingham Forest are understood to have made a fresh bid for Boro midfielder Grant Leadbitter, who Mowbray wants to keep on Teesside.