How does advanced search work?

Question

Google

All good! Tell me, what are the possibilities of advanced search in search engines, what is the syntax of the query? For example, I want to find a person in a certain social network, but only the name, the first letter of the surname and its length are known.
Is it possible to perform a qualitative search with such a data set?

Answer 1

what are the possibilities of advanced search in search engines, what is the query syntax?

https://yandex.ru/support/search/query-language/
https://support.google.com/websearch/answer/2466433

Answer 2

impossible