Create A Row Which "finds" Rows Below That CONTAIN The Same Data

This is a new question based on another thread that contains a solution that I want to tweak.

That thread implements a row that filters the rows below it based on its inputs. Basically, an 'equals' autofilter, but you can type in the criteria in the cells above the column headers instead of going into the autofilter itself.

Here's what I need:
As a variant on that thread, I would like to modify the code to filter on anything that CONTAINS the inputs (not equals).

For example, my Array is A6:K300, with row 6 being column headers, I want Row 5 to essentially be a filter terms row, where I can enter partial phrases in row 5 and have the columns directly beneath them autofilter if the phrase is contained in any of the array rows. If I enter '123' in a cell in row 5, I want the filter results to show '123' and '123R', etc.