Perhaps you should try some spelling variations:
thanh trung » thanh tung
thien hach » thien thanh, hien hanh
hieu cach » hieu cac, chieu sach, hieu ca
trung vat » trung va, trung van, trong vat
dung cong » dung trong
cong bang » cuong bang, dong bang, hong bang
bang phan » nang phan, bang nhan, bang thanh
vat dung » van dung, va dung, viet dung
phan cau » phan dau, phan cac, phan tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thien hach) or (hieu cach)) - thanh trung vat dung cong bang phan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thien hach) OR (hieu cach)) - thanh trung vat dung cong bang phan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((thien hach) or (hieu cach)) - thanh trung vat dung cong bang phan cau*.