When the language is set to be Español in the ArcGIS Online account and ArcGIS Image for ArcGIS Online is licensed for the account if a user attempts to use the raster analysis functionality for the 'Create a raster function template to perform complex processing and analysis' button, the user won't be able to filter the tools.
This issue is not reproducible in the current version of ArcGIS Online and Map Viewer Classic. Searching for 'band' or 'bandas' properly filters to only display raster functions that include those words in their names, returning the same results as when searching for 'band' if the language is set to English. If the issue reoccurs, please contact Esri Support Services.