[Admin Portal] Searching by partial phone no. or email addr doesn't yield desired result

## Background:
Device / Browser (OS version): Chrome on Mac
Build: Version tag 2023-01-31.0, tested on 2023-05-29

## Description:
Given the desired user is `+85298767890` and `ourskydummy@oursky.com`

When searching for `85298767890` or `dummy` , said user is not found. When searching for `+85298767890` or `98767890` or `ourskydummy`, the user can be found

## Steps to reproduce:
1. Login admin portal
2. Choose a project
3. Go to User management
4. (Prepare the specific user)
5. Search for `85298767890` or `dummy`
6. See said user is not found

## Expected result:
Should be able to search by partial phone no or partial email

## Screenshot:

Start at the Admin Portal's User management search entry point and reproduce the case with the supplied phone and email fragments. Trace how those queries are handled, then verify that partial phone and email searches return the expected user while the existing full and suffix searches still work.

Written by the indexing model from the issue text.