this is a humble try to clarify the meanings of these idioms..I hope it will help a bit.
Enlever le pain de la bouche de quelqu`un
To deprive someone of their means of earning a living .
2. Long comme un jour sans pain.
Very long and unbearable situation
3. Avoir du pain sur la planche.
to be very busy doing something
4. Se vendre comme des petits pains.
sell like hot cakes / to be polarized easily / to be influenced easily
5. Pour une bouchée de pain.
For crumbs
6. Coller un pain.
to fist someone on the face
7. Ne pas pouvoir etre au four at au moulin.
can`t do many things at the same time