wheels within wheels(各种影响、原因和行动交织在一起的)错综复杂的情况；复杂的机构；复杂的事情；神秘复杂的原因[过程]

【例句】
There are wheels within wheels in this organization ─ you never really know what is going on.
这个机构里错综复杂，你永远搞不清到底是怎么回事。

Don't lose heart. I know your boss quite well, and there are wheels within wheels.
别灰心。我很了解你的老板，一定有些错综复杂的原因。