The 26-year-old scored for France in their 1-1 draw with Spain in a 2014 World Cup qualifier on Tuesday, and was also on target for the Gunners in their 3-1 win at West Ham United just before the international break.
"There are two things when you are a striker," said Wenger. "First, I'm always worried when a striker doesn't have chances.
"In his case, he always had chances in every single game and couldn't convert them into goals.
"The conversion rate goes in cycles. Once a player starts to score, suddenly he takes off for a while and suddenly it stops again [and] nobody has really found out why. I hope he's at the start of a good cycle."
Giroud joined Arsenal from French champions Montpellier in the summer.