United twice took the lead against Spurs at Old Trafford, first through Rasmus Hojlund and then Marcus Rashford, but goals from Richarlison and Rodrigo Bentancur ensured the visitors took a point back to north London.
Alejandro Garnacho was the one member of United's front three not to get on the scoresheet and he had a tough afternoon against Destiny Udogie, who was largely able to keep the winger quiet.
However, Garnacho felt he should have had a penalty in the first-half, when he went down under close attention from Udogie in the box, but his appeals were swiftly waved away.
Asked post-match if the referee should have pointed to the spot, Ten Hag said: "Yes. What can you do? But I am used to it, all season that is the case," Ten Hag said.
"At Spurs was similar, a clear handball from Romero and I can list a number more. In some point I think it will turn."
United sit seventh in the table after Sunday's draw with Spurs, eight points off Arsenal in fourth having played a game more.
Only three clubs have scored fewer Premier League goals than United this season, but it was the defending that left Ten Hag frustrated against Tottenham.
Richarlison levelled with a header from a corner, before Rodrigo Bentancur struck less than a minute after half-time as United were opened up.
"We have to be more man in certain situations, you have to go up, more physical, head the ball away," Ten Hag said.
"It shouldn't happen. The second [goal] was a typical one. We know the quick releases, we allowed them a diagonal pass and with one diagonal pass they break our whole team. That can't happen."
Ten Hag did though hail the "two great goals" scored by Hojlund and Rashford, and believes his attacking players are at last starting to click into gear.
"You see it's growing," Ten Hag said.
"Add that with the game of Alejandro Garnacho, I think then we have a front three that's a threat for every opponent."