How powerfull is your hood? In my experience, consumer hoods are extremely underpowered. You can make them work, but that involves taking several minutes, even up to 10, at max power to set up a draft that will exhaust fumes from your stove.

It is powerful enough to smoke under it and have it draw out the smoke. It also ate its carbon filter at one point, just sucked it off the grease trap into the fan. I shut the door to the kitchen and open some windows and there is very appreciable draft coming out of those windows. I tend to only use the back two burners directly under the hood while cooking. Certainly no commercial unit, however.

A good test is to see if a piece of paper will stick or fall off (mine will actually keep a plastic tray stuck to it).

Often the problem is the exhaust path, not the extractor itself. Mine has a short straight path with a low resistance terminal cowl.