Dont understand what to do on level 39 use 5 tiles and don't get credit for it....?????

I have help for you. While it seems you aren't getting credit for those words it's because the one or more letters had vines on it. Once those are removed you will get credit when using the letter for the next word. The way to clear the vines is to make 4 letter words which creates a crown. Each crown will take out vines or a letter that's blocking. Also 5+lettered words creates a purple letter which explodes and removes more and combinations do a lot.