Perhaps you should try some spelling variations:
thuoc sac » thuoc sach, thuoc dac, thuoc sai
duc phan » dung phan, duc thang, duc phung
ve triet » va trien, su triet
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
hieu va » lieu va
hanh la » hanh lam, hanh va, hanh ma
sac ky » cac ky, sai ky
la ve » ly ve, ca ve, va ve

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sac ky lang xa hoi. ((hieu va) OR (hieu qua)) cham ((duc phan) or (duc tan)) hanh la ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sac ky lang xa hoi. ((hieu va) OR (hieu qua)) cham ((duc phan) OR (duc tan)) hanh la ve triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sac ky lang xa hoi. ((hieu va) OR (hieu qua)) cham ((duc phan) or (duc tan)) hanh la ve triet".
• Adding a wildcard symbol may retrieve word variants: thuoc sac ky lang xa hoi. ((hieu va) OR (hieu qua)) cham ((duc phan) or (duc tan)) hanh la ve triet*.