Qualitative research means that the nature of the problem can be clear, but it cannot be quantified, that is, it cannot be quantified by establishing a mathematical model. For example, the research on drunk driving belongs to qualitative research, and it can only be said that it is drunk driving, and there cannot be a quantitative thing. We can say that a person's degree of drunk driving varies from 0- 100, and then make a detailed study and finally draw a conclusion. In other words, the results of qualitative research can only be regarded as a general research, and can not be further quantified.

In quantitative research, the problem must be mathematicized, and the significance of the research can be seen intuitively through the numerical results. For example, the troika of China's economic development: investment, consumption and export. So for this study, we can't qualitatively say that exports are the most, followed by investment and consumption, but we must say that the sum of the three is 100, investment is 30, consumption is 25 and export is 45.

In other words, the energy must be quantified, which can only involve some aspects of liberal arts, such as the nature of the research object and can not be quantified, then qualitative research can be used.