The phrase "are poorly labelled" is correct and usable in written English.
It can be used to describe items or elements that are not clearly marked or identified, often leading to confusion or misunderstanding.
Example: "The files in the cabinet are poorly labelled, making it difficult to find the documents we need."
Alternatives: "are inadequately marked" or "are insufficiently identified."
This is nice, for example, if your media files are poorly labeled or if you can't quite remember which was the last episode of Arrested Development you had watched.
In the cerebellar cortex, Purkinje cells are poorly labeled by the cytoplasmic tdT marker, but we observe strong dendrite labeling by the Syp-GFP marker (see Figure 6A, green labeling at the bottom).
Many of these products are poorly labeled and tightly sealed, making it difficult to check the content and quality prior to purchase.
Apple provides a "Reduce Motion" option within the iOS 7 Settings app, but it is poorly labelled; it merely disables the parallax effect, but doesn't stop zooming or sliding.
Moreover, foods and beverages were poorly labelled in spite of strong support from parents for the provision and labelling of healthy food and drink choices in health facilities.
Navigating the main screen menu was straightforward, but the screen icons for key settings like white-balance and focus mode were poorly labeled.
The saikosaponin biosynthesis likely occurs in the meristem, which has plenty of precursors but not saikosaponins; consequently, the meristem was poorly labeled with gold particles (Table 1).
Consistent with these results, MVA particles were poorly labeled with antibodies against the surface of intracellular mature virus but strongly labeled with antibodies against an envelope antigen.
Either they are too small of a collection, they are poorly or partially labeled or they just don't meet your needs.
While some tweets contain valuable information, it is unstructured, poorly labelled and hidden within a larger set of less relevant information.
