PDF error while changing the screen resolution


I am facing issue while extracting data from the PDF when screen resolution changed. Actually i am trying to extract particular data from the scanned PDF file.Since i am using Anchor base with Find image and ‘Get OCR Text’ activity(Google Engine) for extracting particular data.It is working fine when that particular data being visible in the page.Suppose, if i change the screen resolution then that particular data going down, we have to scroll down to visible that data.In this situation i am getting exception like ‘Scrape returned empty text’ or sometimes nothing will be extracted if the selected text doesn’t fit into the screen.I need to extract the data even after changing the screen resolution also.Is there any alternative way in which I could solve the issue?