This should do what you want:
Sub Find_and_Copy():
Dim keywords() As Variant
keywords = Array("Pizza", "Burger", "Chicken")
Dim endRow As Integer
Dim SearchRng As Range
With Sheets("Sheet1")
endRow = .Cells(Rows.Count, "A").End(xlUp).Row
Set SearchRng = .Range("A1:A" & endRow).Cells
End With
Dim r As Range
Dim firstAddress As String
Dim i As Integer
For i = 0 To UBound(keywords):
With SearchRng
Set r = .Find(keywords(i), LookIn:=xlValues)
If Not r Is Nothing Then
firstAddress = r.Address
Do
Cells(r.Row, "B").Value = keywords(i)
Set r = .FindNext(r)
Loop While Not r Is Nothing And r.Address <> firstAddress
End If
End With
Next
End Sub
It will find all occurrences of each entry in the 'keywords' array that matches cells of column "A" - and of course, set column "B" to that keyword.
Note that say you have an entry like "ala Burger Chicken" it'll put 'Chicken' (which I added to 'keywords' just to keep in the spirit of things) in column B for that row because that's the last thing it did a search for - hence overwriting the previous 'Burger' entry that was in that cell.