Who can help me please,what are the most expensive tradinggamecards?

Foil cards, probably?

Are you using Enhanced Steam? It makes it a lot easier to flip through your eligible games and see their values. A few games that I noticed had above average card prices were Contrast, To The Moon, and 100% OJ. But normally, any non-bundle game is more likely to have higher valued cards, since there isn't as many on the market.

As Sisyphus17 suggested, just use Enhanced Steam. Open your badges page in whichever browser you've installed ES into and you can filter the list by "Badges With Card Drops Remaining" and sort it by "Highest Drop Value".