Easy ways to Stop unwanted emails in Gmail.
Sometimes you may get unwanted mail that isn't necessarily spam. Gmail does allow you to create a filter that will send messages from the specified email directly to the trash folder. This will effectively prevent you from having to view messages from the specific email address. Also you can report those 'Gmail users' who is harassing you via emails.
How to create filters in Gmail?:
1. Log in to your
Gmail account.
2. Go to
Settings and Click the
Filter option.
3. Now Create
New filter there.
4. Enter the email address you want to block in the
From field and click the Next Step button.
5. Select the
Delete it option.
6. Now Click the Create Filter button to block all messages from the email address you entered.

Its done.
How to report Harassment from a Gmail user?:
You can Report a Gmail user who has sent messages that violate the Gmail Policies and rules.
To Report user GO HERE