Perhaps you should try some spelling variations:
reflective earlier » reflective learning
based reflective » based selective, based reflections, based receptive
earlier studies » early studies
code based » codes based, mode based, diode based
code case » node case, ode case, made case

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

• Performing a fuzzy search may retrieve terms with similar spellings: commercial ((code case) OR (code based)) based reflective earlier studies.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "commercial ((code case) OR (code based)) based reflective earlier studies.".
• Adding a wildcard symbol may retrieve word variants: commercial ((code case) OR (code based)) based reflective earlier studies.*.