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]