Hello Amir
There are three major contractors that handle employment in Japan right now.
Parcaviation
Hawaiiaviation (CREW)
IAC global
Do a search on those sites about the opportunities available and check their minimums to see if you qualify. Talk to PARC and ask them about a new company coming up that will operate E-170's, I don't know the name of it or the details but I know that PARC just got the contract to supply them with pilots, you might have a better chance if you put your application ahead of the crowd.
Good luck and enjoy Japan