I would like to ask a question about seeking for a job. This job is outside academia, but require many academia skills (such as math, able to deep research, etc). Is this kind of question on topic here? If not, is there a site should I ask instead?
As a rule of thumb, I think that if a job entails publishing in academic journals or work that supports or eventually will lead to that goal, then it's on-topic. Anything that isn't at least tangentially related to that it probably isn't on-topic.
If you are looking help regarding to an R&D job in which people engage in many of the same actions as academia (e.g., scientific research, peer-reviewed publishing, research funding applications), then that job is likely to be considered part of "greater academia" for the purposes of this site.
Broadly speaking, questions about job-seeking outside of academia are not on topic. You may want to try checking out Workplace.SE.
I'm sure there are some counter-examples where questions like this were on topic; if you find any that you want to have clarified, feel free to post in the comments and we can discuss.