Hmmm... I don't now if I can help you but here are my recommantion:
she was pretty korea (It's not like he don't know love, but he chearched for his first love and is a little bit dense to find her) - male lead: workaholic and righteous, female lead: is nice and intelligant
Emergeny couple korea (story of an ex couple, they're working hard to be a doctor and to find themselve again)
Falling for innocence korea (there is a little bit drama in there) - male lead: workaholic and dense, female lead: strong, intelligant
Lucky romance korea - male lead: very dence and workaholic, female lead: nice
Boss&me china - male lead: reserved and workaholic, female lead: naiv and dense
Hotel king korea (a little bit drama) - male lead: reserved, workaholic, female lead: dense and naiv
Just you taiwan - male lead: reserved, dense and workaholic, female lead: strong, dense
Nigeru wa Haji da ga Yaku ni Tatsu japan (It's not like working in the same workplace, but the main lead is very dense and don't know that he is falling in love)
Clean with passion for now korea - male lead: reserved, dense, workaholic, female lead: nice, young
My secret hotel korea( a little bit of drama and ex-lovers) - male lead: reserved and jealous
Refresh man taiwan - male lead: workaholic, reserved, female lead: dense, workaholic
Sweet dreams china - male lead: reserved, workaholic, dense, female lead: naiv, nice
The fox summer china (the second season has more romance) - male lead: reserved, dense, workaholic, female lead: naiv, workaholic, dense
Ugly alert korea (one of the main lead is very dence in topic love)
Ojakgyo Brothers korea (family drama with romance)
I hope there is a drama, that you will like