Rip up and Run down

Rip up verb - Tear into shreds.

Run down and rip up are semantically related. in belittle topic. In some cases you can use "Run down" instead a verb "Rip up", when it comes to topics like criticize very harshly, attack with words.

Run down verb - To come upon after searching, study, or effort.

Rip up and run down are semantically related. Sometimes you can use "Rip up" instead a verb "Run down".