Can’t find the photos taken with Lightroom in my library using iPhone?

Make sure you have the Lightroom tab selected, center bottom of screen. 

In the upper left corner of the image grid it probably says All photos. Tap here to select Lr camera photos. 

If you are taking them from within the Lightroom app then the easiest way to find them may be to look for the Album called Lr Camera Photos (about 4 from the top of the list).

This is an Album that is always standard in the  software.