Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
sach ky » sac ky, sach y, sach ty
vu sach » vu bach, su sach, vu khach
nang xa » nang x, lang xa, nang ma
sang ma » tang ma, nang ma, sang tao
hieu ve » hieu va, hieu van
ve cam » ve cham, ve cac, va cam
luc va » duc va, tuc va, loc va
vi cau » va cau, ve cau, di cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ky ((nang xa) or (sang ma)) hoi. hieu ve cam ((luc va) or (tuc xa)) hanh vi cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky ((nang xa) OR (sang ma)) hoi. hieu ve cam ((luc va) OR (tuc xa)) hanh vi cau tren.
• Adding a wildcard symbol may retrieve word variants: vu sach ky ((nang xa) or (sang ma)) hoi. hieu ve cam ((luc va) or (tuc xa)) hanh vi cau tren*.