Perhaps you should try some spelling variations:
tenth » tent, benth, teeth
kenth » keneth, keith, benth, kanth, kenh
kent » kant, ken
test » text, west, best
problem » problema, problems
problemas » problemaas, problemsas
problemaas » problemaaas, problemsaas, problema, problems, problemes

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "Hilbert's (((tenth OR kenth) OR tenti) OR (kent OR test)) (problem OR (problemas OR problemaas))~".
• Adding a wildcard symbol may retrieve word variants: Hilbert's (((tenth OR kenth) OR tenti) OR (kent OR test)) (problem OR (problemas OR problemaas))*.