Forty-eight hours after his most important victory as president, Jimmy Carter was back before the television cameras yesterday reminding Congress of some of the things it has not done for him lately.

The president turned his attention from the Panama Canal treaties to his battered domestic program, chiefly his salled energy bill, his tax legislation and his proposals for restructuring the civil service.

But it was abundantly clear that, try as he may, it will not be easy for the president to transform the Senate's approval of the canal treaties Tuesday into momentum for other White House initiatives.

In the morning, the president met with three key Democratic members of the House Ways and Means Committe to plead the cause of his tax cut and tax "reform" proposals.

The message Carter receiver in return, particularly concerning the "reform" aspects of the legislation, was "not encouraging," White House press secretary Jody Powell asknowledged.

Later, the president summoned Democratic members of the House Post Office and Civil Service Committee to the White House to discuss another imperiled program that is close to the presidential heart - civil service overhaul.

This activity, and some of the rhetoric that accompanied it, seemed designed to project Carter as more forceful than he has been in the past and to capitalize on the victory on the Panama issue.

But it also carried with it another message: it placed the president in the curious position in an election year of seeming to suggest that American voters blame a Congress controlled by his party for his failure thus far to win passage of major portions of his domestic program.

"We must have energy legislation without further delay, and I call on the Congress to fulfill its duty to the American people," Carter said in his energy statement.

He promised to be firm but to compromise when necessary and, above all to speak for the national interest rather than "the special interests that have hindered our progress so far."

The American people expect these same qualities from the Congress," he concluded.

On the tax legislation, the message, delivered by Powell, was much the same.

If Congress does not act on the Carter tax plan this year, he said, "the dominant economic opinion is that we face prospects ranging from a pause in the (economic) recovery to a recession next year." And in that event. Powell added, "the record will show to whom the question of why should be addressed."

On the civil service proposals, Powell conceded that there is sentiment, particularly in the House, to put the issue off until after this year's elections.

"We don not intend to back down," he said, arguing that passage of the civil service package is "absolutely essential if there is to be any hope of any meaningful reorganization and increased efficiency in the federal government." Until then, he added, all the administration's rhetoric about streamlining the federal bureaucracy will be "worthless."

In the midst of all this activity, there was a reminder of what could be the president's most serious domestic problem - inflation. Carter and Robert S. Strauss, the administration's newly designed anti-inflation counselor, met with a group of top business executives to discuss ways of holding down wages and prices.

Afterward, everyone said the meeting went well. But there was no mention from any of the businessmen of a commitment to two of the president's stated anti-inflation goals- freezing executives salaries and holding wage and price increases this year below their 1976-77 levels.

Near the end of his briefing, Powell was asked wherher his seeming frustration reflected the president's mood. No, he said, "I was trying to sound forceful."%TThat appeared to be the image the White House sought to project yesterday - an image the White House sought to project yesterday - an image that has seldom been associated with Carter during the first 15 months of his presidency.

It may have grown out of the discussions the president had last week with his staff and Cabinet, when he reportedly "talked tough" and told his aides that "the shakedown cruise is over."

But whether this approach will be successful - Carter has been flailing Congress on and off over the energy issue for a year with no discernible effect - was far from clear.

At the very least, Powell suggested, the president intends to be stubborn. Carter plans to send Congress tax "reform" proposals until he walks out of office or it's dealt with effectively.

"You can quit or keep at it," the press secretary said. "We're going to keep at it."