When an e-mail arrives that has 2 specific words in the subject field, I
would like the mail to be moved to a personal archive folder. The 2 words are
not next to each other. For example, Subject field is "This is a test mail",
and the 2 words that I want to look for are "This" and "mail".

The script below is one that works if only 1 word is being checked and
renames the subject line.

Sub ChangeSubjectName(MyMail As MailItem)
Dim strID As String
Dim olNS As Outlook.NameSpace
Dim olMail As Outlook.MailItem

strID = MyMail.EntryID
Set olNS = Application.GetNamespace("MAPI")
Set olMail = olNS.GetItemFromID(strID)
' do stuff with olMail, e.g.

If olMail.Subject = "test" Then
olMail.Subject = "whatever you want the subject to be"
olMail.Save
End If

Set olMail = Nothing
Set olNS = Nothing
End Sub