With accent marks:
Кто в лес, кто по дрова́.
Some to the forest, some for firewood.
Usually this phrase is said with irony and criticism at the same time. It is used in situations when people, seemingly doing the same thing or trying to achieve the same goal, do it without any coordination in their actions so everybody ends up doing his own thing. Therefore, they cannot succeed.
The saying takes an example of a person just walking in the forest and a person gathering firewood: they are both in the forest but are doing different things.
Most often the phrase is used about a discordant singing choir, but can be applied to any action performed by a group of peope.
Other Russian proverbs
One head is good, but two ones are better.
A well-fed man does not understand a starving one.
The forbidden fruit is sweet.
There are no friends for taste and color.
What you will sow, that you will reap.
Start taking care of the dress while it's new, and of your honor while you are young.
Don't bring your set of rules in a foreign monastery
Get your sleigh ready in summer and your (horse-drawn) cart in winter.