Perhaps you should try some spelling variations:
pham thuc » phap thuc, pham chuc, nham thuc
day thanh » dao thanh, dat thanh, da thanh
thu sach » thuat sach, thuoc sach, khau sach
hieu van » hieu va, thien van, lieu va
van pham » san pham, van phan, van phat
thuc day » thuc dan, thuc vat
thanh do » thanh de, thanh pho, thanh hoa
su triet » su viet, su tien, ve triet
tu sach » su sach, te sach, tu cach
y nang » ky nang, ly nang, v nang
do su » do sut, do tu, co su

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) or (((thu sach) OR (thu hoach)))) y nang x ho. hieu van pham thuc day thanh do su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (((thu sach) OR (thu hoach)))) y nang x ho. hieu van pham thuc day thanh do su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (((thu sach) OR (thu hoach)))) y nang x ho. hieu van pham thuc day thanh do su triet".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (((thu sach) OR (thu hoach)))) y nang x ho. hieu van pham thuc day thanh do su triet*.