transfer 搜索节点后选中，再搜索其他关键词时功能异常

[huangxiuqi]

Reproduction link

https://stackblitz.com/edit/ng-zorro-antd-start-jyi6ug?embed=1&file=src/app/app.component.html

Steps to reproduce

左边输入搜索词content1,随便选中几个，再输入搜索词content2，此时上方数字提示会不正确，而且点击转移按钮时，右边没有出现选中的content1的选项，需要两边都改一下搜索词，触发搜索后才会正常

What is expected?

第一种：选中选项后搜索框禁用，不能更改搜索条件，只有没有选中项时才可以搜索
或者第二种：更改搜索词后上方选中数量提示正确，并且转移后右侧可以正常渲染出之前选择的所有选项

What is actually happening?

多次搜索后上方数字提示会不正确，而且点击转移按钮时，右边没有出现选中的content1的选项，需要两边都改一下搜索词，触发搜索后才会正常

Environment	Info
ng-zorro-antd	7.1.0
Browser	Chrome/72.0.3626.121

[ng-zorro-bot]

Translation of this issue:

---

transfer After searching for a node, it is abnormal when searching for other keywords.

Reproduction link

[https://stackblitz.com/edit/ng-zorro-antd-start-jyi6ug?embed=1&file=src/app/app.component.html](https://stackblitz.com/edit/ng-zorro- Antd-start-jyi6ug?embed=1&file=src/app/app.component.html)

Steps to reproduce

Enter the search term content1 on the left, select a few, and then enter the search term content2. At this time, the upper digital prompt will be incorrect, and when the transfer button is clicked, the selected content1 option does not appear on the right side. You need to change the search word on both sides to trigger. Will not work properly after searching

What is expected?

The first type: the search box is disabled after the option is selected, the search condition cannot be changed, and the search condition can be searched only when there is no item selected.
Or the second type: after changing the search term, the selected number above is correct, and after the transfer, the right side can normally render all the previously selected options.

What is actually happening?

After multiple searches, the upper digital prompt will be incorrect, and when the transfer button is clicked, there is no option for the selected content1 on the right side. It is necessary to change the search words on both sides, and the search will be normal after the search is triggered.

Environment	Info
ng-zorro-antd	7.1.0
Browser	Chrome/72.0.3626.121