Perhaps you should try some spelling variations:
cham truc » cau truc, nham thuc, pham thuc
cac khoi » cac thoi, cac khoan, cach thoi
truc van » truc va, thuc van, truc ban
van dung » van dong, xay dung, tin dung
cau tren » cu tren, dau tren, ca tren
so sach » so sanh, bo sach, co sach
ky dang » ky danh
va cham » va chat, va tham
cuu tre » cua tre, cau treo

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ((ky dang) OR (ky nang)) cac khoi. lieu va cham truc van dung tai ((cuu tre) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((ky dang) OR (ky nang)) cac khoi. lieu va cham truc van dung tai ((cuu tre) OR (cau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ((ky dang) OR (ky nang)) cac khoi. lieu va cham truc van dung tai ((cuu tre) or (cau tren))".
• Adding a wildcard symbol may retrieve word variants: so sach ((ky dang) OR (ky nang)) cac khoi. lieu va cham truc van dung tai ((cuu tre) or (cau tren))*.