Perhaps you should try some spelling variations:
dung doi » huong doi, dung tai, dung co
thuc dan » thuc hanh, hoc dan, thuc vat
sach ky » sach y, sach ty, sach kem
doi cua » dai cua, hoi cua
hieu va » lieu va, hieu qua
va cam » va cham, va cac, va cao
tuc va » thuc va, truc va, tuc xa
sac ky » cac ky, sai ky
cua te » cua tu
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu ((sach ky) OR (sac ky)) nang x hoi. hieu va cam ((tuc va) or (thuc dan)) dung doi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu ((sach ky) OR (sac ky)) nang x hoi. hieu va cam ((tuc va) OR (thuc dan)) dung doi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu ((sach ky) OR (sac ky)) nang x hoi. hieu va cam ((tuc va) or (thuc dan)) dung doi cua te".
• Adding a wildcard symbol may retrieve word variants: vu ((sach ky) OR (sac ky)) nang x hoi. hieu va cam ((tuc va) or (thuc dan)) dung doi cua te*.