Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
cau tren » dau tren, ca tren, cau treo
hanh vai » hanh vi, hanh va, hanh tai
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
co thuc » do thuc, co thua, mo thuc
cu tren » tu tren, dua tren
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, me hoi
va co » vo co

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach y nang ((ma hoi) or (ma hoa)). lieu va co thuc va hanh vai ((cau tren) OR (cu tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y nang ((ma hoi) OR (ma hoa)). lieu va co thuc va hanh vai ((cau tren) OR (cu tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y nang ((ma hoi) or (ma hoa)). lieu va co thuc va hanh vai ((cau tren) OR (cu tren))".
• Adding a wildcard symbol may retrieve word variants: toc sach y nang ((ma hoi) or (ma hoa)). lieu va co thuc va hanh vai ((cau tren) OR (cu tren))*.