Perhaps you should try some spelling variations:
nhanh cong » nhanh chong, thanh cong, nganh cong
cong thuc » cong tac
thu sach » tu sach, thuat sach, thuoc sach
sach hoc » cach hoc, sach hoi, mach hoc
mot hoc » mon hoc, mo hoc, bot hoc
thuc ma » thuoc ma, thuc va, thuc ha
van tai » von tai, van tuan
hoa va » hoa van, hoa xa, hoa vo

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach hoc tap, nghien cuu ((mot hoc) OR (mot goc)) nhanh cong thuc ma hoa va van tai~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach hoc tap, nghien cuu ((mot hoc) OR (mot goc)) nhanh cong thuc ma hoa va van tai".
• Adding a wildcard symbol may retrieve word variants: thu sach hoc tap, nghien cuu ((mot hoc) OR (mot goc)) nhanh cong thuc ma hoa va van tai*.