Knows Her Onions?

From one of today's Chemistry "matches":

"Well i can say is I'm good looking ,sincere,hardworking,easy going,love life,love people,caring,loves nature ..not a drinker or a socialite but i do it moderately cos being responsible is my watch word..i never smoke dont think i will ever do it.i love my family ..loves to travel and i thank God for my job cos it involves lot of traveling ..have never been married but i hope i find the right and special woman for me who will compliment me in all ways.

she must be decent,responsible,dont care if she is fat,short,or tall as long as she is good looking and knows her onions ..she ,must be caring,romantic,hard working but dont mind if she haven't got a job..she must be friendly and accommodating,honest ...i know she doesn't have to be perfect Lol cos im not....."

I don't even know what that means so I guess I don't know my onions. Sorry dude.

After laughing and laughing at this dude I looked up "know your onions" AND IT IS A REAL PHRASE -- http://www.phrases.org.uk/meanings/know-your-onions.html. Who knew? I kinda feel bad. But not much. Sorry guy. I take back the mocking tone on that part of your writing ... the rest on the other hand ...