Hello Kasun Bandara,
Thank you for reaching out to Microsoft Support!
You have two different requests with different recipient addresses, one for test.staging@gmail.com and the other for testtaxdome0.staging@gmail.com. If so, inconsistent query results are the expected behavior.
See the documentation for more information about the $search query parameters:
https://zcusa.951200.xyz/en-us/graph/search-query-parameter?tabs=http
Hope this helps.
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