Hi,
As far as I know, we can search the text from html file on a SharePoint-site. Please see the below article:
https://technet.microsoft.com/en-us/library/jj219530.aspx
Then, this issue is more related to the SharePoint search, I recommend you post the question to SharePoint search forum:
https://social.technet.microsoft.com/Forums/en-US/home?forum=sharepointsearch
The reason why we recommend posting appropriately is you will get the most qualified pool of respondents, and other partners who read the forums regularly can either share their knowledge or learn from your interaction with us. Thank you for your understanding.
George ZhaoTechNet Community Support
Yes, but you need to use some JavaScript to interrogate the Visio page. See http://blog.bvisual.net/2014/10/09/using-javascript-to-find-and-highlight-visio-shapes-by-shape-data-values-in-sharepoint-content-editor/
Thanks! I got some answers in that forum.
/Staffan Sderholm
Thanks for your help. I guessed that JavaScript would be the answer but now I know for sure.
/Staffan Sderholm