Search column for location of characters/numbers in cells with different digit lengths

Alright, here goes...
I have a column of values varying from 5 to 18 digits in each cell. I need to be able to search that column for the location of specific numbers and/or characters in the exact pattern specified by the user. Right now I have a userform with 18 textboxes representing the 18 digits. The user can put any letters or numbers in those boxes (1 letter or number per box) and I need to search the column for what they input. From there I just want to highlight the row with any matches.

For example
The column may look like this:

abcd01e2f3g4h5i6jk
lmno89p0q1r2s3t4u5
vwxy67
0123-1234
zabc5d6e7f8g9h0i1j

The user may want to find all instances where there is a '8' in the fifth digit and an 's' in the thirteenth digit(as in the second row).

I tried filling the unused textboxes on the userform with asterisks (*) but that doesn't work for obvious reasons, and question marks (?) only work if each cell contains all 18 digits, which will never be the case.

Digit search userform.jpg

I was hoping this wasn't so hard. Any thoughts anyone? Thanks in advance.