This large-scale eye-movement study (N = 164) investigated how students read short task assignments to complete information search problems and how their cognitive resources are associated with this reading behavior. These cognitive resources include information searching subskills, prior knowledge, verbal memory, reading fluency, and attentional difficulties. In this study, the task assignments consisted of four sentences. The first and last sentences provided context, while the second or third sentence was the relevant or irrelevant sentence under investigation. The results of a linear mixed-model and latent change score analyses showed the ubiquitous influence of reading fluency on first-pass eye movement measures, and the effects of sentence relevancy on making more and longer reinspections and look-backs to the relevant than irrelevant sentence. In addition, the look-backs to the relevant sentence were associated with better information search subskills. Students with attentional difficulties made substantially fewer look-backs specifically to the relevant sentence. These results provide evidence that selective look-backs are used as an important index of comprehension monitoring independent of reading fluency. In this framework, slow reading fluency was found to be associated with laborious decoding but with intact comprehension monitoring, whereas attention difficulty was associated with intact decoding but with deficiency in comprehension monitoring.