[PyMOL] discontiguous surface patches

I want to get surface patches using expand like
select res, resi 14
select patch, res expand 6.0

But  I got some discontiguous surface patches which are not what I want.
How can I get rid of the discontiguous part of surface patches?
Thanks

Bingding


-- 
Bingding Huang
PhD student
Bioinformatics group
Biotec & Department of Computing
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TU Dresden, Germany

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