If you want to categorize or tag documents by keywords, please have a look at the field template 'Tag Document'.
This is how it works: Docparser will scan the text of the whole document, (or your area selection) for specific keywords. Once a keyword is found, a specific category/tag/.. will be returned by the parsing rule. You can define several groups of keywords, one for each category or tag. Each group of keywords is typed into one of the big input fields, each keyword separated by a line break. Next to the keywords, you'll also define the return value in case of a match, (as seen above). If you have any questions or run into trouble getting set up please let us know at firstname.lastname@example.org