"staying unnoticed" is a correct and usable phrase in written English.
You can use it to indicate that something is happening or has happened without anyone noticing. For example, "She snuck out of the house, staying unnoticed by her parents."
Martin does his best to stay unnoticed.
The children are intimidated into silence by their abusers, and the criminals seek to cover their tracks and stay unnoticed.
Like so many other remnants of conflict, the bomb that Chenda brought to the surface may well have stayed unnoticed in the thick river mud, its fins protruding at a sideways angle, had it not caught on the net of a 42-year-old fisherman, Yor Dieb, last month.
Thus, criminals aim to stay unnoticed by the traditional spam filters and avoid drawing attention to abused webmail accounts.
Christmas comes and goes and I try to stay unnoticed.
As everyone in the family was well aware, King's work would stay unnoticed unless someone in her family deliberately promoted it.
Nevertheless, one student suggested to use posters: "I think using posters displaying e.g. the 'healthy eating pyramid' will not stay unnoticed".
However, if the identification of preventive needs is only geared towards the absolute number of OD cases, considerable high risk tasks in rare occupations stay unnoticed.
The differences in wall composition could explain the success of some strains which stay unnoticed by the host through inhibition of apoptosis and ROS but making possible its replication inside PMN as a potential evasion mechanism.
In our case, crucial aspects of the life-history of D. ossarium, namely the very low susceptibility to parasitism and that the species, despite being a spider-hunting wasp, is possibly a significant predator of the most abundant ant species in its range, would have stayed unnoticed if we had only detected the species by molecular methods or if we had only described the species morphologically.
