Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
toc sach » doc sach, thuoc sach, nuoc sach
cau treo » cau theo, cau tren, cau triet
toc sac » toc san, doc sach, tich sac
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
va danh » va dinh, va dan, va hanh
danh va » doanh va, hanh va, anh va
ve cau » ke cau, ve cac, le cau
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 sac) OR (toc sach))) or (hoc sach)) ky nang xa hoi. hieu ve cau tao va danh va cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((toc sac) OR (toc sach))) OR (hoc sach)) ky nang xa hoi. hieu ve cau tao va danh va cau treo.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((toc sac) OR (toc sach))) or (hoc sach)) ky nang xa hoi. hieu ve cau tao va danh va cau treo".
• Adding a wildcard symbol may retrieve word variants: ((((toc sac) OR (toc sach))) or (hoc sach)) ky nang xa hoi. hieu ve cau tao va danh va cau treo*.