Transferring purchases from iPad to iPod

Hi, I have purchased Pop Styles and Piano chords on iPad and can't find the way to transfer purchases to iPod. I always get the message "no purchases to restore" even if the iTunes account is the very same I used for purchase. FAQ say that from i Pod to iPad you have to restore purchases....can't believe the opposite way is not allowed!!!

I have tried the Backup option too...no result!!

SOLVED!.... just had to reinstall iReal Pro on iPod. Thanks anyway :-)

thanks for posting the steps to fix it. Others might find it useful.