Selfish

have designs on

Meaning:

Example: to have a plan or secret desire to get something. Read on

feather one’s (own) nest

Meaning: If you say that you are feathering your own nest, you mean that you are working so hard to gather resources (money) to live a comfortable life in the future.

Example: John is so much concerned about helping others instead of feathering his own nest. Read on

by hook or by crook

Meaning: by any possible means

Example: The farmer will not sell us the land. By hook or by crook, he is hanging on to it. Read on

axe to grind

Meaning: have a private or selfish reason for doing something

Example: He should not become the chairman of the committee as he has too many axes of his own to grind. Read on