How to conduct an effective literature survey in mathematics? Due to Covid, I am unable to go to my University and access the University server. As a result I am unable to use MathSciNet. Is there any other way to do a good and effective literature survey on a topic in Mathematics?
If someone could help me,  I would be  grateful. I am also interested to know how researchers working at Universities that don't have a MathSciNet license conduct research?
Simple answer: There are actually two good and well-known (at least, I had thought so) bibliographic databases for mathematical literature:

MathSciNet

zbMATH


The latter is freely available online as of 2021.
(Of course there are a few differences between them - for instance, the quality of the bibtex entries is a bit better in MathSciNet, in my experience. But anyway, for most purposes both databases do their job quite well.)
Historical Note: While MathSciNet is essentially based on Mathematical Reviews, zbMATH is based on the Zentralblatt für Mathematik - and both the Zentralblatt and Mathematical Reviews were founded by the same person, Otto Neugebauer. I would have called this a fun fact, but unfortunately the historically background (which is described in the previous link) is not particularly funny.