You have a majority of traditionalists on power (60 seats), they have the pass law agenda. If they ask for it, do not negate it.
To improve their approval rating, hover the mouse over the 19 number and you will see what is helping with their approval.
With traditionalist you want to be in peace and keep all deities of the primary religion and high stability.
You also want to keep having traditionalists in power, for that you want to put as much characters of that faction in government positions.
Mouse over the number of seats (60) and you will see the most influential traditionalists in the senate. For other parties do the same. If there is someone very influential you should give him a governorship (small) to negate its senate influence.
When you feel more comfortable playing with politics you may want to invest some time putting your preferred faction in power by selecting characters from that faction in influential positions to switch the control of the senate to that party.
You can read the wiki on government to know about each party:
imperator.paradoxwikis.com