information retrieval ~ finds documents containing 'information' or
'retrieval'
information or retrieval ~ same as above
information and retrieval ~ finds documents containing both 'information' and
'retrieval'
information not retrieval ~ finds documents containing 'information' but not
'retrieval'
(information not retrieval) and WAIS ~ finds documents containing 'WAIS', plus
'information' but not 'retrieval'
web* ~ finds documents containing words starting with 'web'
|