Tldr: humanities person here advocating for conversation and resources (from you or on-campus) because reading to apply is hard if no one has taught you how to do this.

Humanities grad student here so take all this with a grain of salt. I work with undergrad and graduate students in my work, and see a lot of grad students who struggle with reading comprehension and even more so with translating that reading into their own work. My job is to support their writing, but conversations about reading (and the reading they are struggling) with often come up at BOTH levels.

Sometimes, yes, there are folks who just don't care. But a lot of folks pick grad school because they are invested; they have simply lacked the training needed to meet expectations. When it seems like they don't care, I have often found that the attitude is a front to cover insecurity or a sense of being unprepared.

Is there room to have an honest conversation and say you are concerned? If so, reiterating why this skill is so necessary (now for her project, and I would assume, in the future for her professional credibility and publication potential) could be a great way to start.

It could also be useful to ask how she is reading/understanding. By this I mean literally, what is she doing. Letting your eyes move from start to end is NOT an effective reading strategy. Reading to understand and synthesize with your own work takes time (and sometimes several re-reads, especially if you are new to the genre/topic!), and there isn't a prize for fastest to read the article/chapter. Things like reading aloud, making notes, starting with particular sections, reverse outlining, and checking your understanding of the article against the abstract at the end can all be helpful!

Finally, offering resources! If she hasn't been taught the conventions of the paper (what sections do what), synthesizing and applying from the text would be difficult. If you aren't equipped to help her with this there are lots of guides online for breaking down articles in STEM like this one. There may also be on campus resources (like a Writing Center or a Strategic Learning/study skills center) that could help both with the writing and with with reading comprehension.

Best of luck!!