Can't find your symbol? Try clicking on a similar component as there are sub-menus for a lot of these. E.g a P-channel mosfet and an NPN transistor are in the "NMOS" menu.

Does the symbol not exist? Try making your own from the assets and the line/arc tool. E.g a transformer symbol can be made by placing 2 inductors back-to-back with 2 lines between them. Or a fuse can just be made by running a line through a resistor.

When using an asset, it can easily be modified as they are all made with grid-aligned lines/arc/nodes.