Perhaps you should try some spelling variations:
te sach » toc sach
nang ma » tang ma, sang ma, nang cao
hieu su » hieu sau, tieu su, hieu suat
hieu so » thieu so
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa
va cua » va chua, via cua, ca cua

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

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