Perhaps you should try some spelling variations:
bui khac » bui nhat
thanh va » thanh van, hanh va, thanh ha
va thanh » gia thanh, ban thanh, va tinh
hieu van » hieu va, thien van, lieu va
dang cac » dung cac, bang cac, dong cac
dang cay » dang xay, dang ca, dung cay
va triet » va thiet, va trien, ve triet
khac ty » khac thi
nam duc » nam duoc, pham duc, nam thuc
cuu tre » cua tre, cau tren, cau treo

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

• Performing a fuzzy search may retrieve terms with similar spellings: bui khac ty ((dang cay) or (dang cac)) phoi. hieu van nam duc va thanh va ((cuu tre) or (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: bui khac ty ((dang cay) OR (dang cac)) phoi. hieu van nam duc va thanh va ((cuu tre) OR (va triet)).
• Adding a wildcard symbol may retrieve word variants: bui khac ty ((dang cay) or (dang cac)) phoi. hieu van nam duc va thanh va ((cuu tre) or (va triet))*.