When Qian moved out from her first apartment in Paris, she rearranged it to its origianl condition. During the repetitive process of the apartment being "emptied", "refilled" and "emptied" again, the space of Qian's "home" has been shrunken and expanded.
When she was sorting out the memories of the space, she has doubted the facts that was she once existed.
she collected all the dust who is hidden in the space, she was trying to find any evidences to prove her existence in the past year. And to combined the memories and unremarkable things as a way to evoke memories and imaginations.