Match Rows

Hello,
I have several projects that involve this:
The easiest:
I have column A with keywords (10 to 100). Column B has values associated with those words(number of times that search was made in the website). I have to compare from week to week, I can sort the words, but sometimes some of the keywords are missing. It takes too long and too much clicking. And it's prone to errors

Week 1
A=100 keywords B=100 values
Week 2
D=80 keywords E=80 Values
Is there a way that I can just line up the values of week 2 with their corresponding keyword on week 1 so that the worksheet looks like so;
A= n keywords B= Week1 Values C=Week2 Values, etc

Thank you for your help