Where to find graduated text/books?
I would highly recommend  the “汉语教程“ or Hsk标准教程“.
Or just go to google and look for : " hsk sample paper /hsk mock test". You will find plenty of pages that provide previous exam papers with the vocabulary list attached to them. I assume that you are preparing for the hsk3, which the vocab requirement is 600 words right? If I am right, and you prefer to follow textbooks then go for the 汉语教程第一上 and 汉语教程第一下 or simply check out the hsk标准教程3. Those books were published by the Beijing language and culture University press. You can check out their website to get the book that I've listed above. 


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