Perhaps you should try some spelling variations:
trien viet » tieng viet
trinh van » trinh han, trinh quan, trinh toan
hieu viec » nhieu viec, hieu ve, sieu viet
va trinh » van trinh, va tinh, lap trinh
cam thuc » am thuc, nam thuc, cam thu
van cua » vang cua, ban cua, dan cua
thuc va » thuc vat, thuc dan, thuc day
sach ty » sach tu, sach thu, xach tay
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ty) OR (sach y)) nang xa hoi. ((hieu viec) or (trien viet)) cam thuc va trinh van cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach y)) nang xa hoi. ((hieu viec) OR (trien viet)) cam thuc va trinh van cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) OR (sach y)) nang xa hoi. ((hieu viec) or (trien viet)) cam thuc va trinh van cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) OR (sach y)) nang xa hoi. ((hieu viec) or (trien viet)) cam thuc va trinh van cua tre*.