During my writing I discovered some interesting (sub)adventures that my protagonists go through while reaching their end-destination. However, these stories are totally irrelevant to the current plot and structure so I left them out. I was wondering however if anyone has good tips one still planting small hints/pointers towards these adventures, so that I in a future story can go back to these adventures in a seemingly natural way. (does this make sense?)
I'm writing in a third-person "character" mode voice (i.e. only observe/tell what main character does/feels) so I can't basically go writing stuff like "That's a story to be told some other time". I also don't want the 'links/references' to be too obvious: I'm afraid they'l immediately feel out of place if I don't expand on it if the character mentions strange and miraculous adventures that happened in between the whitespace of two chapters.
Thank you in advance.