How to add hint for autocompelete and select like input

Is there a way to add hint like input in select and autocomplete
```
{{#paper-autocomplete
as |autocomplete|
}}

{{paper-autocomplete-highlight
searchText=autocomplete.searchText
flags="i"
}}
{{/paper-autocomplete}}
```

The issue only provides an Ember template using paper-autocomplete and paper-autocomplete-highlight, with no file or test named. Start by locating those components and the related select implementation; the expected hint behavior and completion criteria need to be clarified before work begins.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.