The Toffees' move for Leroy Fer collapsed on transfer deadline day leaving the manager worried that his lack of signings could undermine the club's Champions League hopes
The Toffees' boss still maintains his side have the quality to stick it out until the end of the season but has now begun to believe his small squad may be exposed, following the lack of additions last month.
Everton had almost sealed a move for Dutch international Leroy Fer but the transfer broke down over re-structuring of the contract following complications in the player's medical.
"It wasn't for the want of trying," Moyes told The Guardian.
"We didn't go scattergun at the end when we didn't get Leroy Fer but we tried to add some good players who would make a difference to the first team. And, if that didn't happen, we looked at bringing in young players who could be ones for the future and add value.
"We are disappointed obviously. Fer is a top player and it's a shame it turned out like that, but we are still one of the contenders to be in the top half and in and around the top four."
Young Barnsley defender John Stones was the only January arrival at Goodison Park, with Ross Barkley and Magaye Gueye departing on loan.
"We are short," Moyes added.
"We said before the window opened that we're short of what we want and we tried. But it didn't happen and that's the situation we have to deal with. For different reasons it didn't work out but it wasn't for the want of trying. If there is any criticism then maybe we could have tried a little bit earlier."