Perhaps you should try some spelling variations:
cua thuoc » nha thuoc, cay thuoc, cua nuoc
hoang xa » hoang va, hoang xuan, hoang xanh
hoang ha » hoang hai, hong ha, hoang nham
duoc ma » duoc lam
duoc va » nuoc va, duc va, duong va
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
va hoc » van hoc
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ty ((hoang xa) OR (hoang ha)) hoi. hieu va hoc ((duoc va) or (duoc ma)) hanh vi cua thuoc~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ((hoang xa) OR (hoang ha)) hoi. hieu va hoc ((duoc va) OR (duoc ma)) hanh vi cua thuoc.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty ((hoang xa) OR (hoang ha)) hoi. hieu va hoc ((duoc va) or (duoc ma)) hanh vi cua thuoc".
• Adding a wildcard symbol may retrieve word variants: tu sach ty ((hoang xa) OR (hoang ha)) hoi. hieu va hoc ((duoc va) or (duoc ma)) hanh vi cua thuoc*.