I saved one with "Save As tiff" & and the other as "Save for web jpeg" but these two looks different. Why is tiff less saturated than jpeg, and how to fix this problem?

Probably do to differences in color profiles? Use Bridge "file properties" or your perfected way and tell us what are the color profiles in each image.

If you were using Adobe RGB as your colorspace, doing a Save-As Tiff is going to save it with that same Adobe RGB profile embedded in the image.

When you did Save-for-Web to save as a jpg, it's likely that you had the box checked to auto-convert to sRGB, which is the standard for web output.

So, the tiff one has the AdobeRGB and the jpg one has sRGB. Hence the difference.

I just fixed the problem. Thank you both of you.