The Frenchman has built a strong reputation for plucking the likes of Nicolas Anelka, Robert Pires and Emmanuel Petit from clubs in his homeland and turning them into world class players.
But Wenger, now in his 17th season with the 13 times English champions, has struggled to replicate the successful transfer dealings in recent seasons with Arsenal's last trophy being the 2005 FA Cup.
"The competition is high on the scouting front. The country where we were really, really competitive was France. They produce less players than they did 10, 15 years ago at top, top, top level in France," said Wenger.
"The emerging countries that are producing players look to be Germany and Spain and they have many good young players. They have taken over.
"We are trying to diversify much more where we are looking. In England you are a bit limited.
"I find that a new market that is very interesting and very competitive is the Japanese market. Look at the number of Japanese players who play now in Germany for example."
"It's very difficult because the level of expectation is very high," the manager said.
"People want to see Lionel Messi. They don't want to see a promising guy.
"First of all the name gives hope. When a guy has no name people are already sceptical. So it's much more difficult for us."
Arsenal are sixth in the Premier League after Tuesday's disappointing 1-1 draw at relegation threatened Southampton, who easily restricted Wenger's side with Japan international Maya Yoshida marshalling the Saints backline.
