Again, it'd help if you posted example data. How do I post a question effectively?.

1. classes don't have spaces, elements can have multiple classes, e.g. class="header blue" would apply both the "header" and "blue" classes.

2.

my $html = '<h3>Heading 3.1</h3>
<div>Heading 3.1 content</div>
<h3>Heading 3.2</h3>
<div>Heading 3.2 content</div>';

my $dom = Mojo::DOM->new( $html );
for my $entry ( $dom->find('h3')->each ){
    say $entry->all_text;
}
[download]

output:

Heading 3.1
Heading 3.2
[download]

3.

my $html = '<h3>Heading 3.1</h3>
<span>Heading 3.1 content</span>
<h3>Heading 3.2</h3>
<span>Heading 3.2 content</span>';


my $dom = Mojo::DOM->new( $html );
for my $entry ( $dom->find('h3 + span')->each ){
    say $entry->all_text;
}
[download]

output:

Heading 3.1 content
Heading 3.2 content
[download]

Again, posting some sample data is a better way to get the help you need quicker. See also Mojo::DOM::CSS.

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