Perhaps you should try some spelling variations:
oxford handbooks » oxford handbook, word handbooks, oxford guidebooks
"Oxford handbooks online / Oxford handbooks online" » "Oxford sandboxes online / Oxford sandboxes online", "Oxford handbuch online / Oxford handbuch online", "Oxford handbook define / Oxford handbook define"
oxford redbooks » oxford guidebooks
"Oxford redbooks online / Oxford redbooks online" » "Oxford netbook online / Oxford netbook online"
"oxford handouts online / oxford handouts online" » "oxford handbuch online / oxford handbuch online"
"oxford books online / oxford books online" » "oxford brooks online / oxford brooks online", "oxford book online / oxford book online", "oxford brookes online / oxford brookes online"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (((((("Oxford handbooks online / Oxford handbooks online") OR ("Oxford redbooks online / Oxford redbooks online"))) OR ("oxford handouts online / oxford handouts online"))) OR ("oxford books online / oxford books online")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"Oxford handbooks online / Oxford handbooks online\") OR (\"Oxford redbooks online / Oxford redbooks online\"))) or (\"oxford handouts online / oxford handouts online\"))) or (\"oxford books online / oxford books online\"))".
• Removing quotes may allow a broader search: (((((( Oxford handbooks online / Oxford handbooks online ) OR ( Oxford redbooks online / Oxford redbooks online ))) or ( oxford handouts online / oxford handouts online ))) or ( oxford books online / oxford books online )).
• Adding a wildcard symbol may retrieve word variants: (((((("Oxford handbooks online / Oxford handbooks online") OR ("Oxford redbooks online / Oxford redbooks online"))) or ("oxford handouts online / oxford handouts online"))) or ("oxford books online / oxford books online"))*.