Perhaps you should try some spelling variations:
"Hilbert's benth problem" » "Hilbert's beth problem", "Hilbert's bento problem", "Hilbert's bent problem"
"Hilbert's bench problem" » "Hilbert's berch problem", "Hilbert's beach problem", "Hilbert's bunch problem"
"Hilbert's tenth problems" » "Hilbert's tenti problems", "Hilbert's tent problems", "Hilbert's teeth problems", "Hilbert's tenth problemas", "Hilbert's tenth problema"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("Hilbert's benth problem") OR ("Hilbert's bench problem"))) OR ("Hilbert's tenth problems"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"Hilbert's benth problem\") OR (\"Hilbert's bench problem\"))) OR (\"Hilbert's tenth problems\"))".
• Removing quotes may allow a broader search: (((( Hilbert's benth problem ) OR ( Hilbert's bench problem ))) OR ( Hilbert's tenth problems )).
• Adding a wildcard symbol may retrieve word variants: (((("Hilbert's benth problem") OR ("Hilbert's bench problem"))) OR ("Hilbert's tenth problems"))*.