Perhaps you should try some spelling variations:
"single-less reflex cameras / handbooks OR handbook , manuals, etc" » "single-bass reflex cameras / handbooks OR handbook , manuals, etc", "single-versus reflex cameras / handbooks OR handbook , manuals, etc", "single-loops reflex cameras / handbooks OR handbook , manuals, etc", "single-less reflex camera / handbooks OR handbook , manuals, etc"
"single-lens reflex cameras / handbooks OR handbook , manuals, etc" » "single-les reflex cameras / handbooks OR handbook , manuals, etc", "single-lens reflex camera / handbooks OR handbook , manuals, etc"

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: (("single-lens reflex cameras / (handbooks OR handbook), manuals, etc") OR ("single-less reflex cameras / (handbooks OR handbook), manuals, etc")).
• Removing quotes may allow a broader search: (( single-lens reflex cameras / (handbooks OR handbook), manuals, etc ) or ( single-less reflex cameras / (handbooks OR handbook), manuals, etc )).
• Adding a wildcard symbol may retrieve word variants: (("single-lens reflex cameras / (handbooks OR handbook), manuals, etc") or ("single-less reflex cameras / (handbooks OR handbook), manuals, etc"))*.