This question already has an answer here:
- Can we filter questions by reputation 7 answers
Is it possible to filter questions by reputation of the author?
Just Something like
[favtag] [rep<5] to show all the newcommer questions.
No, this is currently not possible to search based on OP's reputation. You may read all the Advanced Search Options.
On a related note, low rep is not equal to a new commer. You would find users who have been a member of Stack Exchange community for couple of years but their reps are low possibly because they offer frequent bounties or are unable to spend much time here.