vars = []
        query = ""

        words.each do |word|
          query << " or " if query.any?
          query << "name like ? or lastname like ?"
          2.times {vars << "%#{word}%"}
        end

        conditions = []
        conditions << query
        vars.map {|v| conditions << v}


por :

conditions = [""]
words.each do |word|
  conditions.first << " or " if query.any?
  conditions.first << "name like ? or lastname like ?"
  conditions << "%#{word}%"
  conditions << "%#{word}%"
end