Unlike OS X, Windows does not come with any software that can manipulate PDF files. CutePDF is a freeware program that allows you to easily split PDF files from any program that can open them.  Visit cutepdf.com/products/cutepdf/writer.asp and click both "Free Download" and "Free Converter". If you just need to split a single file, you may want to consider using Google Chrome or an online splitting tool, as both of these will be a little faster. This is a good method if you are going to be splitting lots of PDF files. Like most freeware programs, CuteWriter will attempt to install adware during the installation process. Click the Cancel button on the first offer screen, and then click the "Skip this and all remaining" offers link. Click the Setup button to install it automatically. Unlike the "CuteWriter.exe" program, you don't need to worry about adware on this step. CutePDF works from within any program, so open the PDF in Adobe Reader or a web browser. Usually you can just select "File" → "Print" or press Ctrl+P. CutePDF acts as a virtual printer, and creates a PDF file instead of printing the document. By specifying the pages, you'll create a new document from the pages you select. Print button to save the new file. You'll be prompted to give it a name and select the location. Repeat the process if you need to split the original document into multiple new documents.

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Write a summary of the previous text in Vietnamese:
Tải phần mềm CutePDF. Chạy "CuteWriter.exe" để cài đặt phần mềm CutePDF. Chạy chương trình "converter.exe" để cài đặt những tệp cần cho CutePDF. Mở tệp PDF mà bạn muốn tách. Mở trình đơn Print. Chọn "CutePDF Writer" từ danh sách máy in khả dụng. Nhập phần trang mà bạn muốn tách thành tài liệu mới. Nhấn vào nút .