I'm looking for novel similiar to Ryouriban, where the MC's actions helped other people without him knowing.
How about the Other World Dining Hall? http://www.novelupdates.com/series/the-other-world-dining-hall/
http://www.novelupdates.com/series/hp1-kara-hajimeru-isekai-musou/ He meet girls, help them, add them to his harem but he don't know that he is doing that
The Bathroom Goddess: office lady's bathroom window is a portal that connects randomly to different parts of a fantasy world. Each time, she meets someone and helps them out in one way or another, not realising that the help she gives can change the fate of nations.
http://www.novelupdates.com/series/kamigoroshi-no-eiyuu-to-nanatsu-no-seiyaku/ Trust me and i'll bet you like it... He just do what he want, but everyone think he is a saint.. http://www.novelupdates.com/series/the-legendary-moonlight-sculptor/ I trust you already know? I only know that 2, if i know other i think i'll edit this post...
If she got something out of every trade, she would be the ultimate merchant. She barters something she doesn't need, to someone who's desperately in need of that particular kind of thing. Repeatedly. She really knows supply & demand.