Perhaps you should try some spelling variations:
22functional analysis » functional analysis, functional analyses, d functionalanalysis
_ functionalanalysis » 8 funktionalanalysis, v funktionalanalysis, functional analysis
b funktionalanalysis » 8 funktionalanalysis, v funktionalanalysis, uber funktionalanalysis

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: %((((22functional analysis) OR (_ functionalanalysis))) OR (b funktionalanalysis))%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((((22functional analysis) OR (_ functionalanalysis))) or (b funktionalanalysis))%22".
• Adding a wildcard symbol may retrieve word variants: %((((22functional analysis) OR (_ functionalanalysis))) or (b funktionalanalysis))%22*.