Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
nang mai » nang tai, lang mai, nang cai
thuc van » thuc vat, thuc va, thuc hanh
thuc dan » thuc hanh, hoc dan, thuc vat
sach ty » sach y, sach tu, sach thu
hang di » hang doi, hang vi, hang dien
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
di cua » dai cua, doi cua, de cua
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ty ((nang mai) OR (nang ma)) hoi. hieu ve cam ((thuc dan) or (thuc van)) hang di cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((nang mai) OR (nang ma)) hoi. hieu ve cam ((thuc dan) OR (thuc van)) hang di cua triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty ((nang mai) OR (nang ma)) hoi. hieu ve cam ((thuc dan) or (thuc van)) hang di cua triet*".