வளங்கு- is not seems to be a Tamil word.. (but I'm not sure)
கொண்டு- Won't give meaning as single word.
For example,
கொண்டு வா- Bring it (or) Bring here [வா-come]
கொண்டு போ- Take it (or) Take it away [போ-go]
Also in some places it replaces the word 'with (or) using', but only used literally.
For example,
கத்தியை கொண்டு வெட்டு- Cut with the knife (or) Cut using the knife
[கத்தி- Knife; கொண்டு- with or using; வெட்டு-cut]