The south-coast club were beaten 3-0 by Premier League title-hopefuls Chelsea on New Year's Day and have now won only one of their last nine games.
Pochettino's side made a great start to the campaign to move into the top four, but Southampton are now down in ninth place.
Cagliari defender Davide Astori is just one of the players linked with a move to St Mary's Stadium this month, but Pochettino denied any interest in the Italian centre-back.
The Southampton boss is more concerned about getting the likes of Artur Boruc and Victor Wanyama back from injury than bolstering his squad this month.
He said: "Just because we have lost against Chelsea, that doesn't make me interested in the transfer market. The most important thing right now is to recover the players that are injured for us.
"It is very important to keep our best players. But also to recover the players that have been injured for quite a while. To get everybody fit and playing as a unit, that's going to reinforce the squad a lot."
Rickie Lambert has been linked with a move to Premier League rivals West Ham, but Pochettino is not expecting the England striker to leave.
He said: "I know nothing about the potential signing of Rickie Lambert."
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