The definition highlights specified attributes. The source note also explains that an expression can be qualified through an adjective, condition, time, number, or something similar.
Teaching examples:
“Give charity” — no added time or amount stated here.
“Give charity on Friday” — time restriction.
“Bring three books” — number restriction.
“Provide clean cloth” — attribute restriction.
Always identify what exactly is qualified: sometimes it is the object; in other cases it is the act, timing, or manner of performance.