Perhaps you should try some spelling variations:
thuc dan » thuc hanh, hoc dan, thuc vat
dan hanh » dang hanh, dan khanh, dan thanh
cuu thuc » cuu tac
hieu van » hieu va, thien van, lieu va
van cuu » van cau, van chu, van cu
hanh ve » hanh vi, hanh va, hanh kem
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
sach ty » sach tu, sach thu, xach tay
ve cua » le cua, de cua, te cua
cua te » cua tu

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) OR (sach y)) ((nang xa) or (nang ma)) hoi. hieu van cuu thuc dan hanh ve cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach y)) ((nang xa) OR (nang ma)) hoi. hieu van cuu thuc dan hanh ve cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) OR (sach y)) ((nang xa) or (nang ma)) hoi. hieu van cuu thuc dan hanh ve cua te".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) OR (sach y)) ((nang xa) or (nang ma)) hoi. hieu van cuu thuc dan hanh ve cua te*.