Perhaps you should try some spelling variations:
segmental signatures » elemental signatures, elemental signature, dental signatures
segment feature » segment features, segments feature, segmental features
salient feature » salient features

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: line ((((((segment feature) OR (salient feature))) OR (((segment feature) OR (salient feature))s))) OR (segmental signatures)) analysis.
• The words AND, OR and NOT may confuse the search; try adding quotes: "line ((((((segment feature) OR (salient feature))) or (((segment feature) OR (salient feature))s))) or (segmental signatures)) analysis".
• Adding a wildcard symbol may retrieve word variants: line ((((((segment feature) OR (salient feature))) or (((segment feature) OR (salient feature))s))) or (segmental signatures)) analysis*.