Vidic returned to the centre of the United defence in December after injury and his side have since opened up a 15-point lead at the top the Premier League as they close in on a 20th top-flight title.
They have also reached the quarter-finals as they seek a 12th FA Cup, in part to make up for the pain of controversially losing to Real Madrid in the Champions League last 16.
"The international break is good for me. When you have lots of games, like we have recently, you just manage yourself until the next one and you don't work on yourself that much," injury-prone Vidic, 31, told the club's website on Monday.
"Sometimes it is nice to have these days to work on yourself," added the Serbian, who retired from the international set up after his country's failure to reach the 2012 European championship in Poland and Ukraine.
United's defence last conceded a league goal on Jan. 30 and fellow defender Chris Smalling said players recovering from injuries had coincided with the team's improved displays.
"That's linked in with all our defenders coming back now," said Smalling.
"It's just Phil [Jones] who is struggling but I think he will be back soon and our strength is shown by the players that we have available."
United visit FA Cup holders Chelsea in a replay of their last eight clash on April 1 with the winners to play Manchester City in the semi-finals at Wembley on April 14.
