Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
cau tren » cu tren, dau tren, ca tren
ly nang » ky nang, ly hang, ly vang
cam thu » nam thu, cac thu, ca thu
va tich » va tinh, va dich
y nang » ky nang, v nang, may nang
cam tu » nam tu, dam tu, tam tu
va cau » van cau, va cac, va dau

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) or (ly nang)) xa hoi. lieu va ((cam tu) OR (cam thu)) va tich va cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((y nang) OR (ly nang)) xa hoi. lieu va ((cam tu) OR (cam thu)) va tich va cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((y nang) or (ly nang)) xa hoi. lieu va ((cam tu) OR (cam thu)) va tich va cau tren".
• Adding a wildcard symbol may retrieve word variants: toc sach ((y nang) or (ly nang)) xa hoi. lieu va ((cam tu) OR (cam thu)) va tich va cau tren*.