Working with custom records. How to search and update?

I am currently working with custom record types and am trying to achieve 2 things in particular.

1/ Search through a custom record using a search parameter which searches a custom field in the custom record.

2/ Update a custom record with the field that I wish to update is a custom field.

So far this is how far I have got this and the codes works but just retrieves the data.

        public SearchResult assetName2(string machingGroupID)          {              CustomRecordSearch custRecSearch = new CustomRecordSearch();              CustomRecordSearchBasic custRecSearchBasic = new CustomRecordSearchBasic();                          RecordRef recordRef = new RecordRef();              recordRef.internalId = "60";  // id of record type              custRecSearchBasic.recType = recordRef;                custRecSearch.basic = custRecSearchBasic;              _status = _service.login(_passport).status;              SearchResult result = _service.search(custRecSearch);                try              {                  result = _service.search(custRecSearch);                }              catch (Exception ex)              {                  l.wl("N> Add Error: " + ex);                  l.wl("N> Add Error: " + ex.Message);                  throw ex;                }                if (result.status.isSuccess)              {                  l.wl("N> success ");                }              else              {                  l.wl("N> Error ");                }              return result;          }