When you encounter a few documents that can't find full-text resources, you can search in Baidu Academic and google scholar, and sometimes you will give a link to the resources.
In addition, students majoring in computer science can also use the platform of "Academic Model" (the domain name is the pinyin spelling of "Academic Model"), where there are many high-quality foreign documents of computer science, and there are many data statistics and screening functions, which may help you locate valuable documents. In addition, this platform also has the functions of document management and community discussion, which is very suitable for writing graduation thesis in graduation season.