The thing is there really is no "boundary" around "your family tree"
this is one massive database that we all share collaboratively with billions of family records. A single person could very literally be related/connected by blood and marriage to millions of people.
I do think the "familySearch" app (for smart devices) may have a few options in this or related areas - that the computer based web version doesn't.
Lets see what other people say about your question.
As far as I am aware ...
Short Answer: 'No'.
This same question has been asked previously in this Forum and the long established "FamilySearch ("GetSatisfaction") 'Feedback' Forum.
And the answer has always been the same.
Certainly NOT in the "Search" or "Find' feature/facility/function in "Family Tree" of "FamilySearch"; and, the general "Search" feature/facility/function in "FamilySearch".
The options are to, either, look (ie. Search) through the 'Pedigree' page/screen of one's Ancestral lines; and/or, add those in one's Ancestral lines to one's "Watch" List; where, one can "Watch" up to a maximum of 4000 individuals/persons at one time.
I know that this does not help.