Perhaps you should try some spelling variations:
"enhanced vision system" » "enhanced visionen system" (Expand Search)
"Enhanced visionar system" » "Enhanced visionenar system" (Expand Search), "Enhanced missionar system" (Expand Search), "Enhanced visionen system" (Expand Search)
"Enhanced visionenar system" » "Enhanced visionenenar system" (Expand Search), "Enhanced visionen system" (Expand Search)

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"enhanced vision system\") OR (((\"Enhanced visionar system\") OR (\"Enhanced visionenar system\"))))~".
• Removing quotes may allow a broader search: (( enhanced vision system ) OR ((( Enhanced visionar system ) OR ( Enhanced visionenar system ))))~.
• Adding a wildcard symbol may retrieve word variants: (("enhanced vision system") OR ((("Enhanced visionar system") OR ("Enhanced visionenar system"))))*.