Perhaps you should try some spelling variations:
tinh khong » tinh khang, tinh huong, benh khong
khong xuan » thong xuan, khong quan, khong xuong
tinh quan » tinh quang, trinh quan, tin quan
trinh han » trinh quan
hieu soat » hieu suat, hieu hoat, hieu luat
hien soat » thien hoat, kiem soat, bien soan
cho hieu » cao hieu, co hieu, chi hieu
xuan van » luan van, quan van, xuan can
van hien » van hieu, van tien
lan cho » san cho, van cho, han cho

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( ((tinh quan) or (trinh han)) lan cho hieu soat ) or ( tinh khong xuan van hien soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( ((tinh quan) OR (trinh han)) lan cho hieu soat ) OR ( tinh khong xuan van hien soat )).
• Adding a wildcard symbol may retrieve word variants: (( ((tinh quan) or (trinh han)) lan cho hieu soat ) or ( tinh khong xuan van hien soat ))*.