You're not giving us enough information to help you:
You say "some parts of my image turn greyscale"? This is only one image and part are in color and parts in greyscale? Or do you mean "some of my images are turning greyscale"?
What version of InDesign? What file format and color mode are the image(s) in? You can view this information by selecting an image and using the Info panel (Window > Info). Like I'm showing below:
EDIT: I see you said InDesign CC in the title. The current version, InDesign CC 2017?
Typical behavior when viewing a PDF in Apple Preview.