Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, theo sach
hieu cach » hieu cac, chieu sach, hieu ca
trung cap » truong cao, trung tam
trong san » trong cac, cong san, dong san
tung cap » cung cap, thong cap, trong cap
san khau » san pham, san khoa, san phu
khau cap » khan cap, khau cao, khau tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thieu sach) OR (hieu cach)) - thanh ((tung cap) or (trung cap)) dung trong san khau cap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sach) OR (hieu cach)) - thanh ((tung cap) OR (trung cap)) dung trong san khau cap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sach) OR (hieu cach)) - thanh ((tung cap) or (trung cap)) dung trong san khau cap".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) OR (hieu cach)) - thanh ((tung cap) or (trung cap)) dung trong san khau cap*.