Well, 'CH' in stories might represent a code or abbreviation for something unique to that particular narrative. Maybe it's a secret organization, a hidden location, or even a special power. Without more details about the story, it's hard to be sure exactly what it means.
Sure, the Noragami manga is completed. It was a great ride with an ending that wrapped up the plot nicely. If you haven't read it yet, it's worth giving a go.
The 'ch distillery christmas story' might be about the traditions within the distillery during Christmas. For example, they could have a special recipe they only use around Christmas. Or perhaps it's about the people who work there and how they come together to decorate the distillery, share a Christmas meal, and create a festive atmosphere. It could also involve any charity work or community events the distillery participates in during the Christmas season.
If 'ch' refers to a place, perhaps the 'ch secret stories' are historical events that were not widely known. For example, there could be stories about forgotten heroes or mysterious happenings in the area's past. Maybe there were secret alliances or hidden treasures that are part of these stories.