if exist string on other string then do...

hi
i want find string on other big string on the if function
please help me what should i do?

for example:
big string: %album% = asdfghqwertvbn-asdflg
string: "qwert"
i can't use $strstr because this find only first character
i want find all string on other string

In the filter you can use:
%album% HAS qwert

This opinion is not quite right, because the function $strstr does not detect the "first character", ...
but the function $strstr detects the character position, ...
where the search string has been located at first, ...
looking from the left side of the given string to be searched.

If the result of the function $strstr is greater than zero, ...
then the entire search string is member of the big string.
The result from the function $strstr gives the first character position, ...
where the search string has been found within the big string.

DD.20170211.0838.CET