ejm1938

Hi, This situation nearly always causes me problems: I have a minimum hand and open 1d or 1c and hold 3h or 3s. Partner responds 1h or 1s. I don't know if he has 4 or 5 hearts or spades. Almost always when I raise his spade or heart bid, the partnership ends up with only 7 cards for trump suit and usually fails. How should I bid to avoid this problem? Thanks