Perhaps you should try some spelling variations:
khach nhiem » trach nhiem
bat khach » bat khanh, dat khach, vay khach
duoc hoc » quoc hoi
huu loc » muu luoc
hau loc » phau hoc
tu sach » thu sach, su sach, te sach
va nghe » van nghe, va nghi, va nghien
ve nghe » van nghe
tu bat » tu ban, tu dat

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tu bat khach nhiem ((huu loc) or (hau loc)) ) or ( tu sach ((va nghe) OR (ve nghe)) duoc hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu bat khach nhiem ((huu loc) OR (hau loc)) ) OR ( tu sach ((va nghe) OR (ve nghe)) duoc hoc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( tu bat khach nhiem ((huu loc) or (hau loc)) ) or ( tu sach ((va nghe) OR (ve nghe)) duoc hoc ))".
• Adding a wildcard symbol may retrieve word variants: (( tu bat khach nhiem ((huu loc) or (hau loc)) ) or ( tu sach ((va nghe) OR (ve nghe)) duoc hoc ))*.