A period should be used as a place holder for stopwords. Inclusion of stopwords interferes with retrieval. Knowledge' and 'external world' can be anywhere in the title field. The period in 'theory.knowledge' is a place holder for 'of', which is a stopword, hence would interfere with retrieval. The computer will search all fields to find all those records that contain the word 'epistemology' as well as all records that contain 'theory' and 'knowledge', in that order, and no more than one word apart.
Function keys allow various manipulations of records retrieved.
Press the function key while records are being displayed. Online help is available. Enter HELP to display a list of the commands. Enter HELP with a command to display help screens for that command. Precedes search term.