Perhaps you should try some spelling variations:
thuc xay » thuc day, tuc xay, thuat xay
mai duoc » mai quoc, mai duc, mat duoc
tai duoc » tao duoc, tan duoc, ta duoc
xay hanh » day nhanh, day thanh, xanh hanh
nam thuc » nam thuoc, am thuc, nam thu
va nam » van nam, ha nam, va nay
sac ky » cac ky
nang o » nang co, nang ho, nang ro
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sac ky) or (sai ky)) nang o hoi. lieu va nam thuc xay hanh ((tai duoc) OR (mai duoc)) tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sac ky) OR (sai ky)) nang o hoi. lieu va nam thuc xay hanh ((tai duoc) OR (mai duoc)) tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sac ky) or (sai ky)) nang o hoi. lieu va nam thuc xay hanh ((tai duoc) OR (mai duoc)) tren".
• Adding a wildcard symbol may retrieve word variants: tu ((sac ky) or (sai ky)) nang o hoi. lieu va nam thuc xay hanh ((tai duoc) OR (mai duoc)) tren*.