RPG Insanity

The game shows the location of the sub quest givers. I finished the main story, and I am missing sub quests 2, 6, and 20. Anyone knows the location of these sub quests?

Edit: they are found at Zerzi village, which is located east of Grayfang city. Apparently, I completed the story without finding it.

As usual in Exe Create games, NPC dialogues are updated throughout the entire game, and it seems Zerzi Village is Lise's hometown, so I think it doesn't hurt to visit it regularly and as soon as possible, regardless of the side quests being available there.