The Canucks (10-13-2) lost their eighth straight game, matching their longest losing streak since March 26-April 9, 2017.
"We've got to bear down and score, but that's easier said than done in this league," Vancouver coach Travis Green said. "I've said it before: Guys that score a lot of goals in this league get paid a lot of money. We've got to find a way to put pucks in the net. We had some good looks. When you play a team like San Jose, you've got to put your chances in there. They'e a good team, not just offensively, they're a good defensively as well."
Anders Nilsson, who missed 12 games with a broken finger, made 20 saves in his first start since Oct. 25.
The Sharks went 4-1-1 on a six-game homestand, the wins coming against the Canucks, Blues, Nashville Predators and Calgary Flames.
"We had a good homestand when you look at the big picture of it and our record," coach Peter DeBoer said. "Played some tough teams during this homestand and found a way to win some games and did it in different ways too.
"I thought we tightened things up the last few games defensively, got some great goaltending from Dell, some special teams tonight with the power play. [Penalty kill has] been solid the entire time. A lot of good stuff."
San Jose went 3-for-6 on the power play, including two goals in the first period. Vancouver was 0-for-3.
"We want it to be elite, we need it to be elite," DeBoer said of the power play. "It was elite tonight. In the league standings, it's not at elite level yet, but it has the capability of being there. We need it to be elite."
Couture scored on the power play at 10:54 of the first period to give the Sharks a 1-0 lead. Meier made it 2-0 with nine seconds left in the period when he redirected Thornton's shot past Nilsson from close range, also with the man-advantage.
Erik Karlsson scored his second goal of the season from the high slot on the power play to make it 3-0 at 3:43 of the third period. Thornton and Kevin Labanc had the assists.
Karlsson has eight points (two goals, six assists) in the past five games.
"It's getting better and better," Karlsson said. "I think we played well today. Our power play was working well, and we got lots of opportunities. That helped. Obviously, we played well defensively as well. It's nice to see that can come together once in a while. Just got to make it more consistent."
Melker Karlsson made it 4-0 at 9:35 when he redirected Erik Karlsson's point shot past Nilsson for his first goal of the season.
