The uses of 'any'

I’ve used any in the following two sentences:

• “It is clear, also, that when approaching any topics with videos”
• “The main characters in the film are teenagers who attend secondary school and that their problems are related to the problems that any young adults might have”

At first I thought that the problem was that I used ‘any’ (a non-assertive form) in affirmative sentences. Quirk explains that “the contexts which require the any series or ‘non-assertive’ forms chiefly involves

·         The negative not, never, no, neither, nor;
·         The ‘incomplete negatives’ hardly, little, few, least, seldom, etc;
·         The ‘implied negatives’ before; fail, prevent; reluctant, hard, difficult, etc; and comparisons with too;
·         Questions and conditions”

However, Quirk also explains that “as well as their use with plurals and non-count nouns, the determiner any can be used with singular count nouns when they are stressed […] with the special meaning of ‘no matter who, no matter what’:

·         Any apology will satisfy them.
·         He will eat anything.”

That’s the meaning I wanted to imply with my sentences in the paper but I made the mistake of using ‘any’ in that cases with plural nouns. So the sentences should be corrected in the following way:

“It is clear, also, that when approaching any topic with videos”

“The main characters in the film are teenagers who attend secondary school and that their problems are related to the problems that any young adult might have”