What is a victory? Obtaining 1 star. To obtain 1 star when attacking someone you need to deal 50% base damage, destroy the command building, and the final star is awarded by getting 100% damage (but you only need 1).
When selecting someone to attack if you hit Retreat (
button) if you don't want to attack someone, it does not count as a loss. Choose people who look easy and you know you can handle them.
I know its harsh but when you get further in the game you can attack low level people when you are a high level. Just max out the infantry units which cost almost nothing and attacking anyone under 5, you won't get resources but at least you aren't really bullying the low levels because they really have nothing to lose.
When you get to be a higher level and you cannot find lower levels anymore you can cheat the system by making/joining an alliance, search the alliance battle area and fight low levels in alliances (Thanks to Chunkeh Munkeh