title: How to work with nested array in .ts file
body: <p>I have the below json array which my service.ts get request returned. I will like to know how I can grab the value of "university" and "course" from all the objects and store it in a new array. </p>
  
  <p><strong>content of staff array</strong></p>
  
  <pre><code>[
    {"id": 11, "name": "Anna", "education": [
         {"university": "oxford", "course": "administration", "year": "2013"},
         {"university": "lincon", "course": "receptionist", "year": "2010"}
       ]
    },
    {"id": 47, "name": "John", "education": [
         {"university": "toronto", "course": "electrical", "year": "1997"},
         {"university": "ambro", "course": "industrail", "year": "1990"}
       ]
    },
    {"id": 85, "name": "William", "education": [
         {"university": "ambro", "course": "zoology", "year": "2010"},
         {"university": "ambro", "course": "biology", "year": "2001"}
       ]
    }
  ]
  </code></pre>
  
  <p><strong>comp.ts</strong></p>
  
  <pre><code> ngOnInit() {
     this.dataService.getstaff()
        .subscribe((res) =&gt; {
            this.staff = res;
            this.staffDetail = // I want to store education details here
         });
   }
  </code></pre>
  
  <p>How do I apply "find" or "filter" on <strong>staff</strong> array to get value of "university" and "course". How to I code the .ts file. I want the content of <strong>staffDetail</strong> to look like below. </p>
  
  <p><strong>content of staffDetail array</strong></p>
  
  <pre><code>[
  {"education": [
       {"university": "oxford", "course": "administration"},
       {"university": "lincon", "course": "receptionist"}
    ]
  },
  {"education": [
       {"university": "toronto", "course": "electrical"},
       {"university": "ambro", "course": "industrail"}
    ]
  },
  {"education": [
       {"university": "ambro", "course": "zoology"},
       {"university": "ambro", "course": "biology"}
    ]
  }
  ]
  </code></pre>
  
  <p>Do let me know if I need to explain further.</p>