Online search: By using search engines, such as Google and Baidu, enter keywords to find relevant information.
Library retrieval: Searching for books, periodicals, newspapers and other materials related to the theme through the library's bibliography, catalogue, index and other means.
Field investigation: collect information related to the theme through field visits, interviews and observations. Such as questionnaires, interviews, etc.
Collection is an important part of human activities. In ancient times, people's collection behavior was often to meet their own physiological needs, such as eating and drinking, such as defense. With the changes of the times, the collection behavior of human beings has gradually changed. People began to use this skill to penetrate into all areas of life, from obtaining goods to collecting information.