Perhaps you should try some spelling variations:
"Ill-based problems" » "Ill-based problem", "Ill-basic problems", "Ill-based probes"
"ill-mixed problems" » "ill-wicked problems"
"ill-posed problem" » "ill-based problem", "ill-mixed problem"
"Ill-posed problems" » "Ill-based problems", "Ill-mixed problems"

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