How to find the string on .txt

How can I search for the string I want from txt?

For example: search for "AA" or "BB" to find the corresponding position in txt.

I have tried strfind, but he is looking for the starting position of the string, not the position of the entire string.

Answer 1

[Rik]

Use strfind to find the start of a string, then use the length of the input to generate all indices.