To factor $ 6x^3+4xy+3x^2y+2y^2 $ we can use factoring by grouping.
Group $ \color{blue}{ 6x^3 }$ with $ \color{blue}{ 4xy }$ and $ \color{red}{ 3x^2y }$ with $ \color{red}{ 2y^2 }$ then factor each group.
$$ \begin{aligned} 6x^3+4xy+3x^2y+2y^2 &= ( \color{blue}{ 6x^3+4xy } ) + ( \color{red}{ 3x^2y+2y^2 }) = \\ &= \color{blue}{ 2x( 3x^2+2y )} + \color{red}{ y( 3x^2+2y ) } = \\ &= (2x+y)(3x^2+2y) \end{aligned} $$