For the sake of meeting the variable requirements of different quasi-synchronous (QS) frequency-hopping multiple-access (FHMA) communication systems, low-hit-zone (LHZ) frequencyhopping sequence (FHS) sets with flexible parameters and optimal Hamming correlation properties are desired. In this paper, we have a generalized method of constructing LHZ-FHS sets through interleaving technique and analyze the maximum periodic partial Hamming correlation (PPHC) of our constructed LHZ-FHS sets, based on which we are capable of getting four new families of LHZ-FHS sets. It turns out that our new LHZ-FHS sets can be optimal under the PPHC properties and have parameters not covered in the related literature, and thus can be applied in QS-FHMA communication systems to minimize or reduce the mutual-interference. INDEX TERMS Frequency-hopping sequence, low-hit-zone, periodic partial Hamming correlation, interleaving technique.