gain, get, find, earn, acquire, can, may, able to, profit, advantage, benefit
得 centers on obtaining something desirable: gaining, acquiring, or earning. This extends naturally to the idea of being able to do something (having the advantage or benefit that makes it possible).
得 combines 彳 (movement) with 㝵, which likely contributes both sound and the idea of obtaining. The right side 㝵 itself contains 寸 (hand) and an element associated with a shell or treasure, suggesting a hand grasping something valuable.
The left side 彳 suggests going or movement, and the right side 㝵 looks like a hand 寸 reaching for a treasure. Picture going out and grabbing something valuable: you gain it.
For トク, imagine gaining a special talking token that says 'toku' when you earn it: toku -> トク, and the token is your profit.
profit; advantage; benefit; gain
to get; to earn; to acquire; to procure; to gain; to secure; to attain; to obtain; to win
to be able to ...; can ...
obtaining (a qualification, right, object, etc.); acquisition (of land, property, etc.); gaining possession (of); getting; purchase
consent; agreement; acceptance
acquisition; possession
satisfaction; pride; triumph; elation
persuasion
income; earnings
scoring; score; points made; marks obtained; goals; runs
learning; acquisition (of a skill, knowledge, etc.)
number of votes polled; poll votes
knowledge; understanding
bargain; good buy; budget
to make a profit
cannot be helped; unavoidable
good policy; wise policy; best plan
loss and gain; advantage and disadvantage
one's weak point
mastery; learning through experience; realization; realisation; comprehension
bargain; good buy
finding (lost property); picking up
to know; to understand; to be aware of; to regard as; to take for
advantages and disadvantages; plus and minuses