Why wbc went from 5.9, 5.7, 5.1 lymphs 1.5,1.4 and1.0 neutrs steady at 3.7 why did wbc and lymphs go so low read could be weak immune system or cancer?

No meaning by itself: Lab results are just numbers. In real life, numbers change from day to day (that is how nature is). The above numbers are close enough to one another, such that they don't mean anything has changed. It would be very strange and unnatural to get 3 identical results on 3 separate blood tests. So, the numbers don't mean anything without the whole picture... which means asking the doctor for help.