The currently algorithm does give the most relevant search results.
a) Some users may want the search results to be sorted such that all the deprecated modules rank low whereas some may want it to be equal preference as other modules.
b)Currently suppose I give part of the name of a module say "Ref" . In the search results , certain modules with "Ref" even as a part of the module description like Chart search module are currently being given a higher ranking. Sometimes, like in this case , it means that the actual modules being searched for i.e. the modules with "Ref " as part of their module names like Reference application module was ranked low. This is an undesired feature.
For more info , please refer to the discussion here