Search for partial string of numbers

Say I want to find:

5678

In the string 001234567890

how am I suppose to do that?

Somewhere in some Excelsheet I had a phonenumber that started with 00
then cty code/areacode then the actual phonenumber.

Simpy 5678 ? No results.

X1 showed results when indeed I entered the full number, so incl. the leading 00 etc.
but that is after I myself found the excelsheet and tfore knew that all stuff should be added.

Thanks
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