Perhaps you should try some spelling variations:
tang khoa » hang khoa, dang khoa, tang kha
duc manh » suc manh, duc anh, duc minh
khoa hoi » khoan hoi, khoa hoc, khoa doi
tu sach » thu sach, su sach, te sach
cua tre » cuu tre, cua triet, dua tren
hanh ve » hanh vi, hanh va, hanh kem
xuc ban » duc ban, cuc ban, quoc ban
sach ty » sach y, sach tu, sach thu
hieu ve » hieu va, hieu van
ty tang » tay tang, ty xang, ty hang
ve cam » ve cham, ve cac, va cam
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 tang khoa hoi. hieu ve cam ((xuc ban) or (duc manh)) hanh ve ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty tang khoa hoi. hieu ve cam ((xuc ban) OR (duc manh)) hanh ve ((cua tre) OR (cua te)).
• Adding a wildcard symbol may retrieve word variants: tu sach ty tang khoa hoi. hieu ve cam ((xuc ban) or (duc manh)) hanh ve ((cua tre) or (cua te))*.