Set parameters on download metadata to only search for large covers

When I use the function Edit Metadata > Download Metadata and Covers, Calibre normally finds the right covers, although their size and resolution are quite random. More often than not the quality of the covers is very poor.

I have installed the Goodreads plug-in in order to increase the chances of finding a good size and good quality cover, but the final result differ little.

Is there any way to set some parameters so that Calibre only search for large cover images?

Thanks.