Using the Law of Attraction, could I write lists for more than one thing to attract at once?

Sure you could. But writing lists isn’t manifestation.

Thoughts, feelings, words, and actions all have to be aligned to manifest.

The most important part is visualization and make-believe. You have to pretend (and visualize regularly) that what you want is already here.
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Personally, I find it very hard to direct that kind of focus to more than one thing at a time.