Break it into four parts:

(1) IF 
(2) Mouth finds One-Eyed Willy's treasure 
(3) THEN
(4) his family can save their home

This is an "IF,THEN" problem, called a "CONDITIONAL".

The symbols most people use are
Connective	Symbol
Negation	¬  (NOT) sometimes ~
Conjunction	∧  (AND) sometimes &
Disjunction	∨  (OR)  just a capital V
Conditional	→  (IF-THEN) sometimes ⊃ or you can type -->
Biconditional	↔  (IF AND ONLY IF)
Therefore	∴  (THEREFORE)

Choose a capital letter for statement (2), say M, (for its first letter)
Choose → ⊃ for the conditional (IF-THEN)
Choose a capital letter for statement (4), say H, (for its first letter).

Answer:  M → H, or if you prefer M ⊃ H 

Edwin