Query to get only numbers from a string

Question

I have data like this:

string 1: 003Preliminary Examination Plan   
string 2: Coordination005  
string 3: Balance1000sheet

The output I exp

Answer 1

declare @puvodni nvarchar(20)
set @puvodni = N'abc1d8e8ttr987avc'

WHILE PATINDEX('%[^0-9]%', @puvodni) > 0 SET @puvodni = REPLACE(@puvodni, SUBSTRING(@puvodni, PATINDEX('%[^0-9]%', @puvodni), 1), '' ) 

SELECT @puvodni