Here's why:
* "Wooer" has a long "oo" sound, similar to the "oo" in "moon" or "food".
* "Pull" has a short "oo" sound, similar to the "oo" in "book" or "look".
* "Do" has a short "o" sound, similar to the "o" in "hot" or "stop".
So, while all three words contain the letters "oo", they have different pronunciations.