text: The Welsh beat Moldova 4-0 in their first qualifier, but drew against Austria, Georgia and Serbia.
  Chris Coleman's side are third in Group D, four points behind the Republic, who are top.
  "We've been unlucky where we've drawn a few games we felt we should have won," Burnley's Vokes told BBC Radio Wales.
  The side finishing top qualify automatically, with eight of the nine second-placed teams facing play-offs to reach next year's World Cup in Russia.
  Vokes added: "We've been apart for a few months, but if we can look back and take confidence from the last few performances, then I definitely think we can get the right result out there."
  The 27-year-old knows they must win in Dublin to boost their chances of qualifying for a first World Cup since 1958. He says Real Madrid forward Gareth Bale and Arsenal midfielder Aaron Ramsey will provide welcome relief after struggling with injuries this season.
  "It's good news for the team. They're two very important lads in our squad," he added.
  "It's great to see they are back in training and fit and ready to go."
  Burnley travel to the Liberty Stadium on Saturday hoping to seal a win that could send them into the top half of the Premier League table.
  The Clarets lost against Swansea City at home on the opening day and Vokes is aware of the threat they pose given their recent return to form.
  "We know that if we don't get the right result down there then it closes the gap for us [on the relegation zone]," Vokes said.
  "It's important that we get the right results in the next few games to keep that distance between us and the bottom three."
target: Wales forward Sam Vokes hopes they can turn their World Cup qualifying fortunes around when they visit the Republic of Ireland on 24 March.