Perhaps you should try some spelling variations:
"selected tropical diseases" » "neglected tropical diseases", "selected topics diseases", "selected clinical diseases"
"selected tropical disease" » "neglected tropical disease", "selected topics disease", "selected clinical disease"

Try widening your search to All Fields.

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: "((\"selected tropical diseases\") OR (\"selected tropical disease\"))".
• Removing quotes may allow a broader search: (( selected tropical diseases ) OR ( selected tropical disease )).
• Adding a wildcard symbol may retrieve word variants: (("selected tropical diseases") OR ("selected tropical disease"))*.