Perhaps you should try some spelling variations:
cau tren » dau tren, ca tren, cau treo
toc sach » hoc sach, doc sach, thuoc sach
ban tinh » ban thanh, quan tinh, ban hanh
su sach » so sach, vu sach
tinh vi » trinh vi, tinh voi, tinh va
cam cua » ca cua, nam cua, cau cua
cu tren » tu tren, dua tren
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (toc sach)) ky lang xa hoi. hieu ve cam cua ban tinh vi ((cau tren) OR (cu tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (toc sach)) ky lang xa hoi. hieu ve cam cua ban tinh vi ((cau tren) OR (cu tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (toc sach)) ky lang xa hoi. hieu ve cam cua ban tinh vi ((cau tren) OR (cu tren))".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (toc sach)) ky lang xa hoi. hieu ve cam cua ban tinh vi ((cau tren) OR (cu tren))*.