Perhaps you should try some spelling variations:
texti » textil, text, texts
texto » textos
tent » tenti, text, test
problem » problems, problemas
problemass » problemsass, problemasass, problemas, problems, problemes, problemasss
probleme » problemse, problemase, problems, problemas
problema » problemsa, problemasa, problemas

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 ((texti OR texto) OR tent) (problem OR ((problemass OR probleme) OR problema))~".
• Adding a wildcard symbol may retrieve word variants: Hilbert's ((texti OR texto) OR tent) (problem OR ((problemass OR probleme) OR problema))*.