Perhaps you should try some spelling variations:
tenth » benth, teeth, tench, texth, kenth, wenth, trenth
tent » text, kent, went, trent
tenti » texti, kenti, wenti, trenti
ten » tren
test » text, west, best
problem » problems, problemas
problema » problemsa, problemasa, problemas
problematicas » problemsaticas, problemasaticas, problemasticas, problematica

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 tent) OR tenti) OR (ten OR test)) ((problem OR problema) OR problematicas)~".
• Adding a wildcard symbol may retrieve word variants: Hilbert's (((tenth OR tent) OR tenti) OR (ten OR test)) ((problem OR problema) OR problematicas)*.