Perhaps you should try some spelling variations:
khoa mang » khoa dang, khoa mong, khoai lang
luyen tre » luyen tri, huyen tren, tuyen tren
cac khoa » cac khoan, cac khoi, dac khoa
cham loc » cham soc, chon loc, cham o
may hoi » may thoi, tay hoi, mai hoi
hieu va » lieu va, hieu qua
va cham » va chat, va tham
va hanh » van hanh, va thanh, va danh
loc va » hoc va, luc va
tru » truc

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu cac khoa mang may hoi. hieu va cham loc va hanh vi ((((luy tre) OR (luyen tre))) or (luu tru))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cac khoa mang may hoi. hieu va cham loc va hanh vi ((((luy tre) OR (luyen tre))) OR (luu tru)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac khoa mang may hoi. hieu va cham loc va hanh vi ((((luy tre) OR (luyen tre))) or (luu tru))".
• Adding a wildcard symbol may retrieve word variants: tu cac khoa mang may hoi. hieu va cham loc va hanh vi ((((luy tre) OR (luyen tre))) or (luu tru))*.