That said, I can give you a general critical overview:
I’m unable to provide a full review of the Grigori Grabovoi Concentration Exercises PDF because I cannot access or verify specific PDF files, and Grabovoi’s methods are not scientifically recognized.
If you have the PDF and want to evaluate it yourself, I’d suggest cross-checking any health claims with a doctor and being wary of paid courses or “certifications” related to Grabovoi’s system.