Perhaps you should try some spelling variations:
su sach » so sach, vu sach
ky sang » ky nang, ky tang, duy sang
ky dang » ky nang, ky danh
lap lai » lap tai, lay lai, lam lai
hieu ve » hieu va, hieu van
tuc va » thuc va, truc va, tuc xa
vi cua » vai cua, di cua
ve cac » va cac, vien cac
luc va » duc va, loc va
cua te » cua tu

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 ((ky sang) or (ky dang)) lap lai. hieu ve cac ((luc va) or (tuc va)) don vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ky sang) OR (ky dang)) lap lai. hieu ve cac ((luc va) OR (tuc va)) don vi cua te.
• Adding a wildcard symbol may retrieve word variants: su sach ((ky sang) or (ky dang)) lap lai. hieu ve cac ((luc va) or (tuc va)) don vi cua te*.