Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hoa xuat » hoa xa, hoa chat
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
luc van » luoc van, luu van, luc va
duc van » duc va, duc tan, duc manh
hoa cua » hoa chat
va nam » van nam, ha nam, va nay

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky nang xa hoi. hieu va nam ((luc van) OR (duc van)) minh ((hoa cua) or (hoa xuat)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang xa hoi. hieu va nam ((luc van) OR (duc van)) minh ((hoa cua) OR (hoa xuat)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky nang xa hoi. hieu va nam ((luc van) OR (duc van)) minh ((hoa cua) or (hoa xuat)) tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang xa hoi. hieu va nam ((luc van) OR (duc van)) minh ((hoa cua) or (hoa xuat)) tre*.