Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
dung gian » duong gian, dung giao, dung giam
trung su » trung vu, trong su, rung su
trung du » truong du, trung vu, trung dung
hieu ca » hieu cac, hieu cua, hieu va
gian ha » gian dan, gian cua, gian cac
ha cap » hap cap, ha ap, hanh cap

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc ((thieu sach) or (hieu ca)) - thanh ((trung su) or (trung du)) ung dung gian ha cap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((thieu sach) OR (hieu ca)) - thanh ((trung su) OR (trung du)) ung dung gian ha cap.
• Adding a wildcard symbol may retrieve word variants: toc ((thieu sach) or (hieu ca)) - thanh ((trung su) or (trung du)) ung dung gian ha cap*.