The transfer window is set to shut at the end of the month, with the Magpies hoping to sign Crystal Palace star Marc Guehi.
However, Howe believes that retaining the likes of Bruno Guimaraes and Anthony Gordon is as important.
"At the moment, keeping players (this week) is a success, as I sit here today," Howe stated.
"In terms of incomings, that work's still going on behind the scenes.
"A few days left, I think everyone's just trying their best to improve the squad. We will wait and see what happens over the next few days.
"Of course, it only takes one player to make a window a success or failure, however people view it."
Asked if Gordon was having a difficult time amid interest from Liverpool, Howe said: "I don’t know. I think that there’s two ways to look at that. The Euros will have been an incredible experience for him.
"The first time that he will have been with England for any length of time and I’m sure he’ll have learned, seen and experienced a lot from that.
"Sometimes, we all have this vision of the fairytale ending, you go in and help your country win the tournament, but life is rarely like that. Anthony will have seen a lot and hopefully use that for next time that he’s involved."
