`WDIsearch` returns many series which cannot be downloaded

[vincentarelbundock]

This is true even after updating the WDIcache

Can we tell ahead of time and strip those series from search results?

[vincentarelbundock]

Number of variables in cache: 18,978 Number of variables in local: 17,467 Number of variables in cache but not in local ("new variables"): 2,501 Number of variables in local but not in cache ("eliminated variables"): 990