So many methods. Changing of volume, sets, time under tempo, rest period, leverage, mind-muscle recruitment for movement, isometrics, sticking point work. One of the easiest ways to increase strength and size, is via increasing weight. But there are many other methods that can be used. The few I listed, is just scratching the surface.

You remind me of the local coaches in Malaysia.

"Second pull kasi laju!"
"Tangkap bar kasi besar sikit"
"Turun tangkap, laju lagi!"

They always say the obvious, but they don't tell how.

It's like having a dad that tells the son "Make me 1000 grams of gunpowder" but and throws him a box full of various powders, with no instructions.