You can create a new rule for the email you are viewing by swiping left to right and tap on 'New Rule'. This will create new rule fields based on the viewed or selected email. If you select text in an email then you can also use that text as part of the new email rule search.

The new rule dialog will show various field options for the email. You can turn on field like 'From', 'Subject' or 'To'. If you have selected text in the email first then you can use the 'Message' field in the new email rule.
The new rule dialog will also allow you to add text searches to an existing rule that you created earlier. For example you could add new subject search text to another subject search rule.
You can change the search match criteria for each field in the new rule dialog. You can choose to match with 'contains', 'equals', 'ends with' or other options.

After the changes, tap on 'New Rule' to create the new rule. Then you can add a new action to delete the email in the email rule actions section.
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For example if you wanted the rule to match all emails from an email address domain or company, you could choose the following field.
From - Ends with - @example.com
Edit the From address in the new rule dialog to remove the email user address text at the start. Then all emails that are sent from @example.com will match the new rule.


Another example is if you want to block an entire TLD. Perhaps you want to block all email addresses ending with .xyz, .guru, .icu or .buzz You can then change the From field to look like this.
From - Ends with - .xyz


You can also block common spam emails by subject. For example you could add a search field to search for subject.
Subject - Contains - Do a survey and win a free voucher


When you included multiple search fields you will most likely want to use the "or" join option. This way any of the text values you enter can match the rule.
If the option between search field is not "Or" then tap on "And" to switch it to "Or".

Once you have entered the search field, you can choose what actions to perform. For example you could move emails to the spam folder or the trash. eg.
Move to trash
or
Move to Folder - Spam


You can also create your own rules and choose the "From" search field. Enter the search text in the text field beside the new search field.
Then choose and action for the new rule, such as delete or move to folder. More...