Perhaps you should try some spelling variations:
"evidence-based synthesis problems" » "evidence-based synthesis problem"
"evidence-based synthesis process" » "evidence-based synthesis processing", "evidence-based synthesis problem", "evidence-based synthesis properties"
"evidence-acid synthesis process" » "evidence-acid synthesis processing", "evidence-acid synthesis problem", "evidence-acid synthesis properties"

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: (("evidence-based synthesis problems") OR ((("evidence-based synthesis process") OR ("evidence-acid synthesis process")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"evidence-based synthesis problems\") or (((\"evidence-based synthesis process\") OR (\"evidence-acid synthesis process\"))))".
• Removing quotes may allow a broader search: (( evidence-based synthesis problems ) or ((( evidence-based synthesis process ) OR ( evidence-acid synthesis process )))).
• Adding a wildcard symbol may retrieve word variants: (("evidence-based synthesis problems") or ((("evidence-based synthesis process") OR ("evidence-acid synthesis process"))))*.