Combine your terms with the word 'sources' or 'source'
For example, the keyword strategy "vietnam source" brings up
In considering a 'primary source' as opposed to 'secondary source', the difference can be summed up this way: a primary source is a first-hand, original account of events, while a secondary source offers analysis and/or interpretation of the material. In IR/ Political Science, most journal articles would be considered secondary sources.
In general, in Political Science and International Relations there are three categories of primary source material. The first category - the original document - is the most difficult category of information for the researcher to locate and view. Examples might include:
First-person newspaper articles recording an event in the original newspaper (see News media, left)
Government policy documents from the issuing agency - e.g., Foreign Relations of the United States
Congressional record; senate and house hearings - e.g., GPO Access
Original photographs such as those in private collections and library archives.
Most undergraduates and graduate students do not have the luxury of traveling to the central archive of true primary source documents. A number of publishers have compiled collections duplicating original documents in book form; microform, or more recently, image form for the Internet. Since these collections scrupulously aim to reproduce the document format as well as the content, this second category - high-quality reproductions of original documents - can be considered primary source material. Example: Declassified Documents Reference System (DDRS); New York Times (Historical) .
The third category of primary source material consists of reformatted content and translations of original documents. Only the content is 'primary'. While this category of information is certainly easier to locate, and is invaluable in providing access to obscure document content, scholars must take into account the possible human error in the transcription process, and use their best judgment as to the validity and authority of the material in the context of their own research. Example: Yale Avalon project.