clearing search history in mail app

Hello and welcome to Apple Support Communities, Kiran!

We understand you want to clear the search history in the Mail app. We'd be happy to provide information about this.

What you are seeing is not search history, rather search suggestions. It is not possible to disable this. This page guides you on how to efficiently use this feature: Search for messages

"Search using Mail suggestions and filters

1. Start typing your search phrase, then choose one of the suggestions Mail provides.
2. Mail creates a search filter in the search field and lists the matching messages it found in the selected mailbox.
3. To refine the results, do any of the following:

• Change search filters: If a search filter contains an arrow, you can click it to change the filter. For example, you can change a filter to search for messages to or from a certain person, or search subject lines or entire messages.
  • 
• Use multiple search filters: Place the pointer after the first filter, start typing search text, then choose a suggestion. Repeat as needed; the search field scrolls as you add more filters.
  • Mail looks for messages that match all of the filters; the more you use, the more focused the search. If you don’t get expected results, remove some of the filters.
  • Search message headers: Type the name of a message header field, followed by a colon and the value you’re searching for—for example, “from: susan park” or “priority: high”—then choose a suggestion.
  • Search a mailbox that’s not in the Favorites bar: Type the name of the mailbox, choose the Mailbox suggestion, then type what you’re looking for after the Mailbox filter.
  • Search a timeframe or range of dates: Type “date” followed by a colon and a date range, such as “date: 9/05/17-10/05/17.”
• Search using AND, OR, NOT (Boolean operators): Type your search text using the operators (in uppercase). 
  • For example, to search for messages that contain “yellowstone” and “cascades” but not “teton,” type “yellowstone AND cascades NOT teton” or “cascade AND yellowstone -teton.”"

Have a great day!