According to the author of 1 Kings, King Solomon had big boats that sailed far away every three years and came back with treasures like gold and silver, and also brought animals like elephants, monkeys, and pretty birds. This shows that King Solomon was very rich and powerful.
1 Kings 10:22: For the king had at sea a navy of Tharshish with the navy of Hiram: once in three years came the navy of Tharshish, bringing gold, and silver, ivory, and apes, and peacocks. [ivory: or, elephants' teeth]
This verse mentions ships of Tharshish as well, similarly repeating the same information found in 1 Kings 10:22 rather than providing a contradiction.
2 Chronicles 9:21: For the king's ships went to Tarshish with the servants of Huram: every three years once came the ships of Tarshish bringing gold, and silver, ivory, and apes, and peacocks. [ivory: or, elephants' teeth]