Are the visa regulations true that travelers returning to Thailand overland only receive a 15-day visa?

Hi we are flying into Bangkok and have 32 days before we fly out again. We want to make a round trip into Laos, but our problem is, that we have read, that we only get 15 days visa if we return via landborder back to Thailand.

Have someone done it recently and is it true that we get over the land way to Thailand just 15 days?

Thank you in advance 😊