Perhaps you should try some spelling variations:
"23rd ifip study" » "23rd dip study", "23rd itp study", "22nd ifip study"
"23rd rflp study" » "23rd help study", "23rd nlp study", "23rd rhp study"
"23rd ii study" » "23rd icmi study", "23rd hci study", "23rd i.e study"

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: (("23rd ii study") OR ((("23rd ifip study") OR ("23rd rflp study")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"23rd ii study\") or (((\"23rd ifip study\") OR (\"23rd rflp study\"))))".
• Removing quotes may allow a broader search: (( 23rd ii study ) or ((( 23rd ifip study ) OR ( 23rd rflp study )))).
• Adding a wildcard symbol may retrieve word variants: (("23rd ii study") or ((("23rd ifip study") OR ("23rd rflp study"))))*.