Search capability for existing SQL Server records in ASP.Net Core with Razor pages

I have an app which already:
displays a list of existing SQL Server records from a table
gives the user the option of adding a record by showing a form with blank fields to be filled in.

I have been unsuccessful trying to find help developing a search option, whereby a window is shown identical to the "add record" window, but the user is invited to enter a partial value in one or more of the fields, then the computer returns a list of only the records which have field values containing that partial value.

You will probably get more help with this on an ASP.Net site.

Thank you!
I have seen the link to this page before, but I haven't yet succeeded at implementing it.
I'll try yet again. Maybe one of these days, it will work.