However, if the questionnaire could not be designed appropriately, the question in it will lead to misunderstanding. So, there is only one chance to change some questions before handing out questionnaire. Accordingly, it also causes another problem the researcher is not able to explore the detailed and potential information but only based on the questions in the questionnaire. In general, the method is inclined to combine with qualitative method like interview because it is beneficial to collect more accurate and comprehensive data (Greener, 2011, p.8).
As a result, more papers are prone to adopt a combining quantitative and qualitative method through data collection and content comparative analysis. A mixed method is also called triangulation. A successful triangulation as a useful approach will take full advantage of the superiority of quantitative and qualitative method to obtain reliable and real data (Alston and bowles, 2003, p.64). For example, observation and interview can be combined to