Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
ky lang » ky nang, ky tang, tay lang
ky dang » ky nang, ky danh
hieu va » lieu va, hieu qua
xuc van » luc van, vuc van, xuc ban
duc van » duc va, duc tan, duc manh
cuu tre » cua tre, cau tren, cau treo
va cam » va cham, va cac, va cao
vi cuu » vi luu, vinh cuu

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 ((ky lang) OR (ky dang)) xa hoi. hieu va cam ((xuc van) or (duc van)) hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky lang) OR (ky dang)) xa hoi. hieu va cam ((xuc van) OR (duc van)) hanh vi cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky lang) OR (ky dang)) xa hoi. hieu va cam ((xuc van) or (duc van)) hanh vi cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky lang) OR (ky dang)) xa hoi. hieu va cam ((xuc van) or (duc van)) hanh vi cuu tre*.