Scotland slipped to the basement of Europe's Group A on Friday when Macedonia beat Wales 2-1 ahead of Belgium's 2-0 victory at Hampden.
The Scots could still finish third but, with only Croatia at Hampden to come after facing Macedonia on Tuesday night, they need to pick up a result in Skopje.
Griffiths told the Scottish Football Association website: "We want to get as far up the table as possible and finish the campaign strongly. We have only got two games left so hopefully we can get six points from them.
"We knew it would be a difficult game on Friday and we know it will be the same on Tuesday as well."
Griffiths is looking to retain his starting place after a lively display against the Belgians, although his best work was done near the halfway line as Scotland struggled to support the Wolves forward.
The former Hibernian player, who has scored four goals in as many matches for Wolves, said: "It was great to finally get my debut in Croatia and I managed to get on at Wembley and start on Friday as well, so I'm hoping that continues for a long time.
"I'm hoping to get game time, but that's up to the manager to decide if he wants to start with me or put me on the bench and I can have an impact from the bench,
"But whatever team he puts out I'm sure we will do well."
Griffiths was replaced by Jordan Rhodes midway through the second half against Belgium but the Blackburn forward is out of the Macedonia trip with a hand injury.
That leaves Nottingham Forest forward Jamie Mackie and Leeds striker Ross McCormack as competition for a place up front.
Strachan also lost Charlie Adam, who was an unused substitute against Belgium, with a back injury.
Scotland boss Strachan was already without goalkeeper Allan McGregor and Hull team-mate George Boyd, West Brom midfielders Graham Dorrans and James Morrison through injury along with longer-term absentees Darren Fletcher, Gary Caldwell and Steven Fletcher.
Norwich winger Robert Snodgrass is suspended after his booking against Belgium.