Using dataset from Dataset of Vietnamese students' learning habits during COVID-19 by Trung et al. (2020), this paper answer two research questions. First, should any items be dropped to improve alpha co-efficient? Second, do the items measure one of the three concepts (Necessity for self-learning during COVID-19, Effectiveness for self-learning activities, and Acquired knowledge during COVID-19 teaching online session) the authors of the study intended? The result shows that nothing would be changed to improve alpha co-efficient, yet some items should be modified or omitted for better factor analysis results.